辛星解读laravel源代码第一篇即Database的实现流程

<?phpnamespace Illuminate\Database\Query;use Closure;use BadMethodCallException;use Illuminate\Support\Arr;use Illuminate\Support\Str;use InvalidArgumentException;use Illuminate\Support\Collection;use Illuminate\Pagination\Paginator;use Illuminate\Contracts\Support\Arrayable;use Illuminate\Database\ConnectionInterface;use Illuminate\Database\Query\Grammars\Grammar;use Illuminate\Pagination\LengthAwarePaginator;use Illuminate\Database\Query\Processors\Processor;class Builder{    /**     * The database connection instance.     *     * @var \Illuminate\Database\Connection     */    protected $connection;    /**     * The database query grammar instance.     *     * @var \Illuminate\Database\Query\Grammars\Grammar     */    protected $grammar;    /**     * The database query post processor instance.     *     * @var \Illuminate\Database\Query\Processors\Processor     */    protected $processor;    /**     * The current query value bindings.     *     * @var array     */    protected $bindings = [        'select' => [],        'join'   => [],        'where'  => [],        'having' => [],        'order'  => [],    ];    /**     * An aggregate function and column to be run.     *     * @var array     */    public $aggregate;    /**     * The columns that should be returned.     *     * @var array     */    public $columns;    /**     * Indicates if the query returns distinct results.     *     * @var bool     */    public $distinct = false;    /**     * The table which the query is targeting.     *     * @var string     */    public $from;    /**     * The table joins for the query.     *     * @var array     */    public $joins;    /**     * The where constraints for the query.     *     * @var array     */    public $wheres;    /**     * The groupings for the query.     *     * @var array     */    public $groups;    /**     * The having constraints for the query.     *     * @var array     */    public $havings;    /**     * The orderings for the query.     *     * @var array     */    public $orders;    /**     * The maximum number of records to return.     *     * @var int     */    public $limit;    /**     * The number of records to skip.     *     * @var int     */    public $offset;    /**     * The query union statements.     *     * @var array     */    public $unions;    /**     * The maximum number of union records to return.     *     * @var int     */    public $unionLimit;    /**     * The number of union records to skip.     *     * @var int     */    public $unionOffset;    /**     * The orderings for the union query.     *     * @var array     */    public $unionOrders;    /**     * Indicates whether row locking is being used.     *     * @var string|bool     */    public $lock;    /**     * The field backups currently in use.     *     * @var array     */    protected $backups = [];    /**     * All of the available clause operators.     *     * @var array     */    protected $operators = [        '=', '', '=', '', '!=',        'like', 'like binary', 'not like', 'between', 'ilike',        '&', '|', '^', '>',        'rlike', 'regexp', 'not regexp',        '~', '~*', '!~', '!~*', 'similar to',                'not similar to',    ];    /**     * Whether use write pdo for select.     *     * @var bool     */    protected $useWritePdo = false;    /**     * Create a new query builder instance.     *     * @param  \Illuminate\Database\ConnectionInterface  $connection     * @param  \Illuminate\Database\Query\Grammars\Grammar  $grammar     * @param  \Illuminate\Database\Query\Processors\Processor  $processor     * @return void     */    public function __construct(ConnectionInterface $connection,                                Grammar $grammar,                                Processor $processor)    {        $this->grammar = $grammar;        $this->processor = $processor;        $this->connection = $connection;    }    /**     * Set the columns to be selected.     *     * @param  array  $columns     * @return $this     */    public function select($columns = ['*'])    {        $this->columns = is_array($columns) ? $columns : func_get_args();        return $this;    }    /**     * Add a new "raw" select expression to the query.     *     * @param  string  $expression     * @param  array   $bindings     * @return \Illuminate\Database\Query\Builder|static     */    public function selectRaw($expression, array $bindings = [])    {        $this->addSelect(new Expression($expression));        if ($bindings) {            $this->addBinding($bindings, 'select');        }        return $this;    }    /**     * Add a subselect expression to the query.     *     * @param  \Closure|\Illuminate\Database\Query\Builder|string $query     * @param  string  $as     * @return \Illuminate\Database\Query\Builder|static     */    public function selectSub($query, $as)    {        if ($query instanceof Closure) {            $callback = $query;            $callback($query = $this->newQuery());        }        if ($query instanceof self) {            $bindings = $query->getBindings();            $query = $query->toSql();        } elseif (is_string($query)) {            $bindings = [];        } else {            throw new InvalidArgumentException;        }        return $this->selectRaw('('.$query.') as '.$this->grammar->wrap($as), $bindings);    }    /**     * Add a new select column to the query.     *     * @param  mixed  $column     * @return $this     */    public function addSelect($column)    {        $column = is_array($column) ? $column : func_get_args();        $this->columns = array_merge((array) $this->columns, $column);        return $this;    }    /**     * Force the query to only return distinct results.     *     * @return $this     */    public function distinct()    {        $this->distinct = true;        return $this;    }    /**     * Set the table which the query is targeting.     *     * @param  string  $table     * @return $this     */    public function from($table)    {        $this->from = $table;        return $this;    }    /**     * Add a join clause to the query.     *     * @param  string  $table     * @param  string  $one     * @param  string  $operator     * @param  string  $two     * @param  string  $type     * @param  bool    $where     * @return $this     */    public function join($table, $one, $operator = null, $two = null, $type = 'inner', $where = false)    {        // If the first "column" of the join is really a Closure instance the developer        // is trying to build a join with a complex "on" clause containing more than        // one condition, so we'll add the join and call a Closure with the query.        if ($one instanceof Closure) {            $this->joins[] = new JoinClause($type, $table);            call_user_func($one, end($this->joins));        }        // If the column is simply a string, we can assume the join simply has a basic        // "on" clause with a single condition. So we will just build the join with        // this simple join clauses attached to it. There is not a join callback.        else {            $join = new JoinClause($type, $table);            $this->joins[] = $join->on(                $one, $operator, $two, 'and', $where            );        }        return $this;    }    /**     * Add a "join where" clause to the query.     *     * @param  string  $table     * @param  string  $one     * @param  string  $operator     * @param  string  $two     * @param  string  $type     * @return \Illuminate\Database\Query\Builder|static     */    public function joinWhere($table, $one, $operator, $two, $type = 'inner')    {        return $this->join($table, $one, $operator, $two, $type, true);    }    /**     * Add a left join to the query.     *     * @param  string  $table     * @param  string  $first     * @param  string  $operator     * @param  string  $second     * @return \Illuminate\Database\Query\Builder|static     */    public function leftJoin($table, $first, $operator = null, $second = null)    {        return $this->join($table, $first, $operator, $second, 'left');    }    /**     * Add a "join where" clause to the query.     *     * @param  string  $table     * @param  string  $one     * @param  string  $operator     * @param  string  $two     * @return \Illuminate\Database\Query\Builder|static     */    public function leftJoinWhere($table, $one, $operator, $two)    {        return $this->joinWhere($table, $one, $operator, $two, 'left');    }    /**     * Add a right join to the query.     *     * @param  string  $table     * @param  string  $first     * @param  string  $operator     * @param  string  $second     * @return \Illuminate\Database\Query\Builder|static     */    public function rightJoin($table, $first, $operator = null, $second = null)    {        return $this->join($table, $first, $operator, $second, 'right');    }    /**     * Add a "right join where" clause to the query.     *     * @param  string  $table     * @param  string  $one     * @param  string  $operator     * @param  string  $two     * @return \Illuminate\Database\Query\Builder|static     */    public function rightJoinWhere($table, $one, $operator, $two)    {        return $this->joinWhere($table, $one, $operator, $two, 'right');    }    /**     * Add a basic where clause to the query.     *     * @param  string|array|\Closure  $column     * @param  string  $operator     * @param  mixed   $value     * @param  string  $boolean     * @return $this     *     * @throws \InvalidArgumentException     */    public function where($column, $operator = null, $value = null, $boolean = 'and')    {        // If the column is an array, we will assume it is an array of key-value pairs        // and can add them each as a where clause. We will maintain the boolean we        // received when the method was called and pass it into the nested where.        if (is_array($column)) {            return $this->whereNested(function ($query) use ($column) {                foreach ($column as $key => $value) {                    $query->where($key, '=', $value);                }            }, $boolean);        }        // Here we will make some assumptions about the operator. If only 2 values are        // passed to the method, we will assume that the operator is an equals sign        // and keep going. Otherwise, we'll require the operator to be passed in.        if (func_num_args() == 2) {            list($value, $operator) = [$operator, '='];        } elseif ($this->invalidOperatorAndValue($operator, $value)) {            throw new InvalidArgumentException('Illegal operator and value combination.');        }        // If the columns is actually a Closure instance, we will assume the developer        // wants to begin a nested where statement which is wrapped in parenthesis.        // We'll add that Closure to the query then return back out immediately.        if ($column instanceof Closure) {            return $this->whereNested($column, $boolean);        }        // If the given operator is not found in the list of valid operators we will        // assume that the developer is just short-cutting the '=' operators and        // we will set the operators to '=' and set the values appropriately.        if (!in_array(strtolower($operator), $this->operators, true)) {            list($value, $operator) = [$operator, '='];        }        // If the value is a Closure, it means the developer is performing an entire        // sub-select within the query and we will need to compile the sub-select        // within the where clause to get the appropriate query record results.        if ($value instanceof Closure) {            return $this->whereSub($column, $operator, $value, $boolean);        }        // If the value is "null", we will just assume the developer wants to add a        // where null clause to the query. So, we will allow a short-cut here to        // that method for convenience so the developer doesn't have to check.        if (is_null($value)) {            return $this->whereNull($column, $boolean, $operator != '=');        }        // Now that we are working with just a simple query we can put the elements        // in our array and add the query binding to our array of bindings that        // will be bound to each SQL statements when it is finally executed.        $type = 'Basic';        $this->wheres[] = compact('type', 'column', 'operator', 'value', 'boolean');        if (!$value instanceof Expression) {            $this->addBinding($value, 'where');        }        return $this;    }    /**     * Add an "or where" clause to the query.     *     * @param  string  $column     * @param  string  $operator     * @param  mixed   $value     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhere($column, $operator = null, $value = null)    {        return $this->where($column, $operator, $value, 'or');    }    /**     * Determine if the given operator and value combination is legal.     *     * @param  string  $operator     * @param  mixed  $value     * @return bool     */    protected function invalidOperatorAndValue($operator, $value)    {        $isOperator = in_array($operator, $this->operators);        return $isOperator && $operator != '=' && is_null($value);    }    /**     * Add a raw where clause to the query.     *     * @param  string  $sql     * @param  array   $bindings     * @param  string  $boolean     * @return $this     */    public function whereRaw($sql, array $bindings = [], $boolean = 'and')    {        $type = 'raw';        $this->wheres[] = compact('type', 'sql', 'boolean');        $this->addBinding($bindings, 'where');        return $this;    }    /**     * Add a raw or where clause to the query.     *     * @param  string  $sql     * @param  array   $bindings     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereRaw($sql, array $bindings = [])    {        return $this->whereRaw($sql, $bindings, 'or');    }    /**     * Add a where between statement to the query.     *     * @param  string  $column     * @param  array   $values     * @param  string  $boolean     * @param  bool  $not     * @return $this     */    public function whereBetween($column, array $values, $boolean = 'and', $not = false)    {        $type = 'between';        $this->wheres[] = compact('column', 'type', 'boolean', 'not');        $this->addBinding($values, 'where');        return $this;    }    /**     * Add an or where between statement to the query.     *     * @param  string  $column     * @param  array   $values     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereBetween($column, array $values)    {        return $this->whereBetween($column, $values, 'or');    }    /**     * Add a where not between statement to the query.     *     * @param  string  $column     * @param  array   $values     * @param  string  $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereNotBetween($column, array $values, $boolean = 'and')    {        return $this->whereBetween($column, $values, $boolean, true);    }    /**     * Add an or where not between statement to the query.     *     * @param  string  $column     * @param  array   $values     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereNotBetween($column, array $values)    {        return $this->whereNotBetween($column, $values, 'or');    }    /**     * Add a nested where statement to the query.     *     * @param  \Closure $callback     * @param  string   $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereNested(Closure $callback, $boolean = 'and')    {        // To handle nested queries we'll actually create a brand new query instance        // and pass it off to the Closure that we have. The Closure can simply do        // do whatever it wants to a query then we will store it for compiling.        $query = $this->newQuery();        $query->from($this->from);        call_user_func($callback, $query);        return $this->addNestedWhereQuery($query, $boolean);    }    /**     * Add another query builder as a nested where to the query builder.     *     * @param  \Illuminate\Database\Query\Builder|static $query     * @param  string  $boolean     * @return $this     */    public function addNestedWhereQuery($query, $boolean = 'and')    {        if (count($query->wheres)) {            $type = 'Nested';            $this->wheres[] = compact('type', 'query', 'boolean');            $this->mergeBindings($query);        }        return $this;    }    /**     * Add a full sub-select to the query.     *     * @param  string   $column     * @param  string   $operator     * @param  \Closure $callback     * @param  string   $boolean     * @return $this     */    protected function whereSub($column, $operator, Closure $callback, $boolean)    {        $type = 'Sub';        $query = $this->newQuery();        // Once we have the query instance we can simply execute it so it can add all        // of the sub-select's conditions to itself, and then we can cache it off        // in the array of where clauses for the "main" parent query instance.        call_user_func($callback, $query);        $this->wheres[] = compact('type', 'column', 'operator', 'query', 'boolean');        $this->mergeBindings($query);        return $this;    }    /**     * Add an exists clause to the query.     *     * @param  \Closure $callback     * @param  string   $boolean     * @param  bool     $not     * @return $this     */    public function whereExists(Closure $callback, $boolean = 'and', $not = false)    {        $type = $not ? 'NotExists' : 'Exists';        $query = $this->newQuery();        // Similar to the sub-select clause, we will create a new query instance so        // the developer may cleanly specify the entire exists query and we will        // compile the whole thing in the grammar and insert it into the SQL.        call_user_func($callback, $query);        $this->wheres[] = compact('type', 'operator', 'query', 'boolean');        $this->mergeBindings($query);        return $this;    }    /**     * Add an or exists clause to the query.     *     * @param  \Closure $callback     * @param  bool     $not     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereExists(Closure $callback, $not = false)    {        return $this->whereExists($callback, 'or', $not);    }    /**     * Add a where not exists clause to the query.     *     * @param  \Closure $callback     * @param  string   $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereNotExists(Closure $callback, $boolean = 'and')    {        return $this->whereExists($callback, $boolean, true);    }    /**     * Add a where not exists clause to the query.     *     * @param  \Closure  $callback     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereNotExists(Closure $callback)    {        return $this->orWhereExists($callback, true);    }    /**     * Add a "where in" clause to the query.     *     * @param  string  $column     * @param  mixed   $values     * @param  string  $boolean     * @param  bool    $not     * @return $this     */    public function whereIn($column, $values, $boolean = 'and', $not = false)    {        $type = $not ? 'NotIn' : 'In';        // If the value of the where in clause is actually a Closure, we will assume that        // the developer is using a full sub-select for this "in" statement, and will        // execute those Closures, then we can re-construct the entire sub-selects.        if ($values instanceof Closure) {            return $this->whereInSub($column, $values, $boolean, $not);        }        if ($values instanceof Arrayable) {            $values = $values->toArray();        }        $this->wheres[] = compact('type', 'column', 'values', 'boolean');        $this->addBinding($values, 'where');        return $this;    }    /**     * Add an "or where in" clause to the query.     *     * @param  string  $column     * @param  mixed   $values     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereIn($column, $values)    {        return $this->whereIn($column, $values, 'or');    }    /**     * Add a "where not in" clause to the query.     *     * @param  string  $column     * @param  mixed   $values     * @param  string  $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereNotIn($column, $values, $boolean = 'and')    {        return $this->whereIn($column, $values, $boolean, true);    }    /**     * Add an "or where not in" clause to the query.     *     * @param  string  $column     * @param  mixed   $values     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereNotIn($column, $values)    {        return $this->whereNotIn($column, $values, 'or');    }    /**     * Add a where in with a sub-select to the query.     *     * @param  string   $column     * @param  \Closure $callback     * @param  string   $boolean     * @param  bool     $not     * @return $this     */    protected function whereInSub($column, Closure $callback, $boolean, $not)    {        $type = $not ? 'NotInSub' : 'InSub';        // To create the exists sub-select, we will actually create a query and call the        // provided callback with the query so the developer may set any of the query        // conditions they want for the in clause, then we'll put it in this array.        call_user_func($callback, $query = $this->newQuery());        $this->wheres[] = compact('type', 'column', 'query', 'boolean');        $this->mergeBindings($query);        return $this;    }    /**     * Add a "where null" clause to the query.     *     * @param  string  $column     * @param  string  $boolean     * @param  bool    $not     * @return $this     */    public function whereNull($column, $boolean = 'and', $not = false)    {        $type = $not ? 'NotNull' : 'Null';        $this->wheres[] = compact('type', 'column', 'boolean');        return $this;    }    /**     * Add an "or where null" clause to the query.     *     * @param  string  $column     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereNull($column)    {        return $this->whereNull($column, 'or');    }    /**     * Add a "where not null" clause to the query.     *     * @param  string  $column     * @param  string  $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereNotNull($column, $boolean = 'and')    {        return $this->whereNull($column, $boolean, true);    }    /**     * Add an "or where not null" clause to the query.     *     * @param  string  $column     * @return \Illuminate\Database\Query\Builder|static     */    public function orWhereNotNull($column)    {        return $this->whereNotNull($column, 'or');    }    /**     * Add a "where date" statement to the query.     *     * @param  string  $column     * @param  string   $operator     * @param  int   $value     * @param  string   $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereDate($column, $operator, $value, $boolean = 'and')    {        return $this->addDateBasedWhere('Date', $column, $operator, $value, $boolean);    }    /**     * Add a "where day" statement to the query.     *     * @param  string  $column     * @param  string   $operator     * @param  int   $value     * @param  string   $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereDay($column, $operator, $value, $boolean = 'and')    {        return $this->addDateBasedWhere('Day', $column, $operator, $value, $boolean);    }    /**     * Add a "where month" statement to the query.     *     * @param  string  $column     * @param  string   $operator     * @param  int   $value     * @param  string   $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereMonth($column, $operator, $value, $boolean = 'and')    {        return $this->addDateBasedWhere('Month', $column, $operator, $value, $boolean);    }    /**     * Add a "where year" statement to the query.     *     * @param  string  $column     * @param  string   $operator     * @param  int   $value     * @param  string   $boolean     * @return \Illuminate\Database\Query\Builder|static     */    public function whereYear($column, $operator, $value, $boolean = 'and')    {        return $this->addDateBasedWhere('Year', $column, $operator, $value, $boolean);    }    /**     * Add a date based (year, month, day) statement to the query.     *     * @param  string  $type     * @param  string  $column     * @param  string  $operator     * @param  int  $value     * @param  string  $boolean     * @return $this     */    protected function addDateBasedWhere($type, $column, $operator, $value, $boolean = 'and')    {        $this->wheres[] = compact('column', 'type', 'boolean', 'operator', 'value');        $this->addBinding($value, 'where');        return $this;    }    /**     * Handles dynamic "where" clauses to the query.     *     * @param  string  $method     * @param  string  $parameters     * @return $this     */    public function dynamicWhere($method, $parameters)    {        $finder = substr($method, 5);        $segments = preg_split('/(And|Or)(?=[A-Z])/', $finder, -1, PREG_SPLIT_DELIM_CAPTURE);        // The connector variable will determine which connector will be used for the        // query condition. We will change it as we come across new boolean values        // in the dynamic method strings, which could contain a number of these.        $connector = 'and';        $index = 0;        foreach ($segments as $segment) {            // If the segment is not a boolean connector, we can assume it is a column's name            // and we will add it to the query as a new constraint as a where clause, then            // we can keep iterating through the dynamic method string's segments again.            if ($segment != 'And' && $segment != 'Or') {                $this->addDynamic($segment, $connector, $parameters, $index);                $index++;            }            // Otherwise, we will store the connector so we know how the next where clause we            // find in the query should be connected to the previous ones, meaning we will            // have the proper boolean connector to connect the next where clause found.            else {                $connector = $segment;            }        }        return $this;    }    /**     * Add a single dynamic where clause statement to the query.     *     * @param  string  $segment     * @param  string  $connector     * @param  array   $parameters     * @param  int     $index     * @return void     */    protected function addDynamic($segment, $connector, $parameters, $index)    {        // Once we have parsed out the columns and formatted the boolean operators we        // are ready to add it to this query as a where clause just like any other        // clause on the query. Then we'll increment the parameter index values.        $bool = strtolower($connector);        $this->where(Str::snake($segment), '=', $parameters[$index], $bool);    }    /**     * Add a "group by" clause to the query.     *     * @param  array|string  $column,...     * @return $this     */    public function groupBy()    {        foreach (func_get_args() as $arg) {            $this->groups = array_merge((array) $this->groups, is_array($arg) ? $arg : [$arg]);        }        return $this;    }    /**     * Add a "having" clause to the query.     *     * @param  string  $column     * @param  string  $operator     * @param  string  $value     * @param  string  $boolean     * @return $this     */    public function having($column, $operator = null, $value = null, $boolean = 'and')    {        $type = 'basic';        $this->havings[] = compact('type', 'column', 'operator', 'value', 'boolean');        if (!$value instanceof Expression) {            $this->addBinding($value, 'having');        }        return $this;    }    /**     * Add a "or having" clause to the query.     *     * @param  string  $column     * @param  string  $operator     * @param  string  $value     * @return \Illuminate\Database\Query\Builder|static     */    public function orHaving($column, $operator = null, $value = null)    {        return $this->having($column, $operator, $value, 'or');    }    /**     * Add a raw having clause to the query.     *     * @param  string  $sql     * @param  array   $bindings     * @param  string  $boolean     * @return $this     */    public function havingRaw($sql, array $bindings = [], $boolean = 'and')    {        $type = 'raw';        $this->havings[] = compact('type', 'sql', 'boolean');        $this->addBinding($bindings, 'having');        return $this;    }    /**     * Add a raw or having clause to the query.     *     * @param  string  $sql     * @param  array   $bindings     * @return \Illuminate\Database\Query\Builder|static     */    public function orHavingRaw($sql, array $bindings = [])    {        return $this->havingRaw($sql, $bindings, 'or');    }    /**     * Add an "order by" clause to the query.     *     * @param  string  $column     * @param  string  $direction     * @return $this     */    public function orderBy($column, $direction = 'asc')    {        $property = $this->unions ? 'unionOrders' : 'orders';        $direction = strtolower($direction) == 'asc' ? 'asc' : 'desc';        $this->{$property}[] = compact('column', 'direction');        return $this;    }    /**     * Add an "order by" clause for a timestamp to the query.     *     * @param  string  $column     * @return \Illuminate\Database\Query\Builder|static     */    public function latest($column = 'created_at')    {        return $this->orderBy($column, 'desc');    }    /**     * Add an "order by" clause for a timestamp to the query.     *     * @param  string  $column     * @return \Illuminate\Database\Query\Builder|static     */    public function oldest($column = 'created_at')    {        return $this->orderBy($column, 'asc');    }    /**     * Add a raw "order by" clause to the query.     *     * @param  string  $sql     * @param  array  $bindings     * @return $this     */    public function orderByRaw($sql, $bindings = [])    {        $property = $this->unions ? 'unionOrders' : 'orders';        $type = 'raw';        $this->{$property}[] = compact('type', 'sql');        $this->addBinding($bindings, 'order');        return $this;    }    /**     * Set the "offset" value of the query.     *     * @param  int  $value     * @return $this     */    public function offset($value)    {        $property = $this->unions ? 'unionOffset' : 'offset';        $this->$property = max(0, $value);        return $this;    }    /**     * Alias to set the "offset" value of the query.     *     * @param  int  $value     * @return \Illuminate\Database\Query\Builder|static     */    public function skip($value)    {        return $this->offset($value);    }    /**     * Set the "limit" value of the query.     *     * @param  int  $value     * @return $this     */    public function limit($value)    {        $property = $this->unions ? 'unionLimit' : 'limit';        if ($value > 0) {            $this->$property = $value;        }        return $this;    }    /**     * Alias to set the "limit" value of the query.     *     * @param  int  $value     * @return \Illuminate\Database\Query\Builder|static     */    public function take($value)    {        return $this->limit($value);    }    /**     * Set the limit and offset for a given page.     *     * @param  int  $page     * @param  int  $perPage     * @return \Illuminate\Database\Query\Builder|static     */    public function forPage($page, $perPage = 15)    {        return $this->skip(($page - 1) * $perPage)->take($perPage);    }    /**     * Add a union statement to the query.     *     * @param  \Illuminate\Database\Query\Builder|\Closure  $query     * @param  bool  $all     * @return \Illuminate\Database\Query\Builder|static     */    public function union($query, $all = false)    {        if ($query instanceof Closure) {            call_user_func($query, $query = $this->newQuery());        }        $this->unions[] = compact('query', 'all');        return $this->mergeBindings($query);    }    /**     * Add a union all statement to the query.     *     * @param  \Illuminate\Database\Query\Builder|\Closure  $query     * @return \Illuminate\Database\Query\Builder|static     */    public function unionAll($query)    {        return $this->union($query, true);    }    /**     * Lock the selected rows in the table.     *     * @param  bool  $value     * @return $this     */    public function lock($value = true)    {        $this->lock = $value;        return $this;    }    /**     * Lock the selected rows in the table for updating.     *     * @return \Illuminate\Database\Query\Builder     */    public function lockForUpdate()    {        return $this->lock(true);    }    /**     * Share lock the selected rows in the table.     *     * @return \Illuminate\Database\Query\Builder     */    public function sharedLock()    {        return $this->lock(false);    }    /**     * Get the SQL representation of the query.     *     * @return string     */    public function toSql()    {        return $this->grammar->compileSelect($this);    }    /**     * Execute a query for a single record by ID.     *     * @param  int    $id     * @param  array  $columns     * @return mixed|static     */    public function find($id, $columns = ['*'])    {        return $this->where('id', '=', $id)->first($columns);    }    /**     * Get a single column's value from the first result of a query.     *     * @param  string  $column     * @return mixed     */    public function value($column)    {        $result = (array) $this->first([$column]);        return count($result) > 0 ? reset($result) : null;    }    /**     * Get a single column's value from the first result of a query.     *     * This is an alias for the "value" method.     *     * @param  string  $column     * @return mixed     *     * @deprecated since version 5.1.     */    public function pluck($column)    {        return $this->value($column);    }    /**     * Execute the query and get the first result.     *     * @param  array   $columns     * @return mixed|static     */    public function first($columns = ['*'])    {        $results = $this->take(1)->get($columns);        return count($results) > 0 ? reset($results) : null;    }    /**     * Execute the query as a "select" statement.     *     * @param  array  $columns     * @return array|static[]     */    public function get($columns = ['*'])    {        return $this->getFresh($columns);    }    /**     * Execute the query as a fresh "select" statement.     *     * @param  array  $columns     * @return array|static[]     */    public function getFresh($columns = ['*'])    {        if (is_null($this->columns)) {            $this->columns = $columns;        }        return $this->processor->processSelect($this, $this->runSelect());    }    /**     * Run the query as a "select" statement against the connection.     *     * @return array     */    protected function runSelect()    {        return $this->connection->select($this->toSql(), $this->getBindings(), !$this->useWritePdo);    }    /**     * Paginate the given query into a simple paginator.     *     * @param  int  $perPage     * @param  array  $columns     * @param  string  $pageName     * @return \Illuminate\Contracts\Pagination\LengthAwarePaginator     */    public function paginate($perPage = 15, $columns = ['*'], $pageName = 'page')    {        $page = Paginator::resolveCurrentPage($pageName);        $total = $this->getCountForPagination($columns);        $results = $this->forPage($page, $perPage)->get($columns);        return new LengthAwarePaginator($results, $total, $perPage, $page, [            'path' => Paginator::resolveCurrentPath(),            'pageName' => $pageName,        ]);    }    /**     * Get a paginator only supporting simple next and previous links.     *     * This is more efficient on larger data-sets, etc.     *     * @param  int  $perPage     * @param  array  $columns     * @param  string  $pageName     * @return \Illuminate\Contracts\Pagination\Paginator     */    public function simplePaginate($perPage = 15, $columns = ['*'], $pageName = 'page')    {        $page = Paginator::resolveCurrentPage($pageName);        $this->skip(($page - 1) * $perPage)->take($perPage + 1);        return new Paginator($this->get($columns), $perPage, $page, [            'path' => Paginator::resolveCurrentPath(),            'pageName' => $pageName,        ]);    }    /**     * Get the count of the total records for the paginator.     *     * @param  array  $columns     * @return int     */    public function getCountForPagination($columns = ['*'])    {        $this->backupFieldsForCount();        $this->aggregate = ['function' => 'count', 'columns' => $columns];        $results = $this->get();        $this->aggregate = null;        $this->restoreFieldsForCount();        if (isset($this->groups)) {            return count($results);        }        return isset($results[0]) ? (int) array_change_key_case((array) $results[0])['aggregate'] : 0;    }    /**     * Backup some fields for the pagination count.     *     * @return void     */    protected function backupFieldsForCount()    {        foreach (['orders', 'limit', 'offset', 'columns'] as $field) {            $this->backups[$field] = $this->{$field};            $this->{$field} = null;        }    }    /**     * Restore some fields after the pagination count.     *     * @return void     */    protected function restoreFieldsForCount()    {        foreach (['orders', 'limit', 'offset', 'columns'] as $field) {            $this->{$field} = $this->backups[$field];        }        $this->backups = [];    }    /**     * Chunk the results of the query.     *     * @param  int  $count     * @param  callable  $callback     * @return void     */    public function chunk($count, callable $callback)    {        $results = $this->forPage($page = 1, $count)->get();        while (count($results) > 0) {            // On each chunk result set, we will pass them to the callback and then let the            // developer take care of everything within the callback, which allows us to            // keep the memory low for spinning through large result sets for working.            if (call_user_func($callback, $results) === false) {                break;            }            $page++;            $results = $this->forPage($page, $count)->get();        }    }    /**     * Get an array with the values of a given column.     *     * @param  string  $column     * @param  string  $key     * @return array     */    public function lists($column, $key = null)    {        $columns = $this->getListSelect($column, $key);        $results = new Collection($this->get($columns));        return $results->pluck($columns[0], Arr::get($columns, 1))->all();    }    /**     * Get the columns that should be used in a list array.     *     * @param  string  $column     * @param  string  $key     * @return array     */    protected function getListSelect($column, $key)    {        $select = is_null($key) ? [$column] : [$column, $key];        // If the selected column contains a "dot", we will remove it so that the list        // operation can run normally. Specifying the table is not needed, since we        // really want the names of the columns as it is in this resulting array.        return array_map(function ($column) {            $dot = strpos($column, '.');            return $dot === false ? $column : substr($column, $dot + 1);        }, $select);    }    /**     * Concatenate values of a given column as a string.     *     * @param  string  $column     * @param  string  $glue     * @return string     */    public function implode($column, $glue = null)    {        if (is_null($glue)) {            return implode($this->lists($column));        }        return implode($glue, $this->lists($column));    }    /**     * Determine if any rows exist for the current query.     *     * @return bool     */    public function exists()    {        $limit = $this->limit;        $result = $this->limit(1)->count() > 0;        $this->limit($limit);        return $result;    }    /**     * Retrieve the "count" result of the query.     *     * @param  string  $columns     * @return int     */    public function count($columns = '*')    {        if (!is_array($columns)) {            $columns = [$columns];        }        return (int) $this->aggregate(__FUNCTION__, $columns);    }    /**     * Retrieve the minimum value of a given column.     *     * @param  string  $column     * @return float|int     */    public function min($column)    {        return $this->aggregate(__FUNCTION__, [$column]);    }    /**     * Retrieve the maximum value of a given column.     *     * @param  string  $column     * @return float|int     */    public function max($column)    {        return $this->aggregate(__FUNCTION__, [$column]);    }    /**     * Retrieve the sum of the values of a given column.     *     * @param  string  $column     * @return float|int     */    public function sum($column)    {        $result = $this->aggregate(__FUNCTION__, [$column]);        return $result ?: 0;    }    /**     * Retrieve the average of the values of a given column.     *     * @param  string  $column     * @return float|int     */    public function avg($column)    {        return $this->aggregate(__FUNCTION__, [$column]);    }    /**     * Execute an aggregate function on the database.     *     * @param  string  $function     * @param  array   $columns     * @return float|int     */    public function aggregate($function, $columns = ['*'])    {        $this->aggregate = compact('function', 'columns');        $previousColumns = $this->columns;        $results = $this->get($columns);        // Once we have executed the query, we will reset the aggregate property so        // that more select queries can be executed against the database without        // the aggregate value getting in the way when the grammar builds it.        $this->aggregate = null;        $this->columns = $previousColumns;        if (isset($results[0])) {            $result = array_change_key_case((array) $results[0]);            return $result['aggregate'];        }    }    /**     * Insert a new record into the database.     *     * @param  array  $values     * @return bool     */    public function insert(array $values)    {        if (empty($values)) {            return true;        }        // Since every insert gets treated like a batch insert, we will make sure the        // bindings are structured in a way that is convenient for building these        // inserts statements by verifying the elements are actually an array.        if (!is_array(reset($values))) {            $values = [$values];        }        // Since every insert gets treated like a batch insert, we will make sure the        // bindings are structured in a way that is convenient for building these        // inserts statements by verifying the elements are actually an array.        else {            foreach ($values as $key => $value) {                ksort($value);                $values[$key] = $value;            }        }        // We'll treat every insert like a batch insert so we can easily insert each        // of the records into the database consistently. This will make it much        // easier on the grammars to just handle one type of record insertion.        $bindings = [];        foreach ($values as $record) {            foreach ($record as $value) {                $bindings[] = $value;            }        }        $sql = $this->grammar->compileInsert($this, $values);        // Once we have compiled the insert statement's SQL we can execute it on the        // connection and return a result as a boolean success indicator as that        // is the same type of result returned by the raw connection instance.        $bindings = $this->cleanBindings($bindings);        return $this->connection->insert($sql, $bindings);    }    /**     * Insert a new record and get the value of the primary key.     *     * @param  array   $values     * @param  string  $sequence     * @return int     */    public function insertGetId(array $values, $sequence = null)    {        $sql = $this->grammar->compileInsertGetId($this, $values, $sequence);        $values = $this->cleanBindings($values);        return $this->processor->processInsertGetId($this, $sql, $values, $sequence);    }    /**     * Update a record in the database.     *     * @param  array  $values     * @return int     */    public function update(array $values)    {        $bindings = array_values(array_merge($values, $this->getBindings()));        $sql = $this->grammar->compileUpdate($this, $values);        return $this->connection->update($sql, $this->cleanBindings($bindings));    }    /**     * Increment a column's value by a given amount.     *     * @param  string  $column     * @param  int     $amount     * @param  array   $extra     * @return int     */    public function increment($column, $amount = 1, array $extra = [])    {        $wrapped = $this->grammar->wrap($column);        $columns = array_merge([$column => $this->raw("$wrapped + $amount")], $extra);        return $this->update($columns);    }    /**     * Decrement a column's value by a given amount.     *     * @param  string  $column     * @param  int     $amount     * @param  array   $extra     * @return int     */    public function decrement($column, $amount = 1, array $extra = [])    {        $wrapped = $this->grammar->wrap($column);        $columns = array_merge([$column => $this->raw("$wrapped - $amount")], $extra);        return $this->update($columns);    }    /**     * Delete a record from the database.     *     * @param  mixed  $id     * @return int     */    public function delete($id = null)    {        // If an ID is passed to the method, we will set the where clause to check        // the ID to allow developers to simply and quickly remove a single row        // from their database without manually specifying the where clauses.        if (!is_null($id)) {            $this->where('id', '=', $id);        }        $sql = $this->grammar->compileDelete($this);        return $this->connection->delete($sql, $this->getBindings());    }    /**     * Run a truncate statement on the table.     *     * @return void     */    public function truncate()    {        foreach ($this->grammar->compileTruncate($this) as $sql => $bindings) {            $this->connection->statement($sql, $bindings);        }    }    /**     * Get a new instance of the query builder.     *     * @return \Illuminate\Database\Query\Builder     */    public function newQuery()    {        return new static($this->connection, $this->grammar, $this->processor);    }    /**     * Merge an array of where clauses and bindings.     *     * @param  array  $wheres     * @param  array  $bindings     * @return void     */    public function mergeWheres($wheres, $bindings)    {        $this->wheres = array_merge((array) $this->wheres, (array) $wheres);        $this->bindings['where'] = array_values(array_merge($this->bindings['where'], (array) $bindings));    }    /**     * Remove all of the expressions from a list of bindings.     *     * @param  array  $bindings     * @return array     */    protected function cleanBindings(array $bindings)    {        return array_values(array_filter($bindings, function ($binding) {            return !$binding instanceof Expression;        }));    }    /**     * Create a raw database expression.     *     * @param  mixed  $value     * @return \Illuminate\Database\Query\Expression     */    public function raw($value)    {        return $this->connection->raw($value);    }    /**     * Get the current query value bindings in a flattened array.     *     * @return array     */    public function getBindings()    {        return Arr::flatten($this->bindings);    }    /**     * Get the raw array of bindings.     *     * @return array     */    public function getRawBindings()    {        return $this->bindings;    }    /**     * Set the bindings on the query builder.     *     * @param  array   $bindings     * @param  string  $type     * @return $this     *     * @throws \InvalidArgumentException     */    public function setBindings(array $bindings, $type = 'where')    {        if (!array_key_exists($type, $this->bindings)) {            throw new InvalidArgumentException("Invalid binding type: {$type}.");        }        $this->bindings[$type] = $bindings;        return $this;    }    /**     * Add a binding to the query.     *     * @param  mixed   $value     * @param  string  $type     * @return $this     *     * @throws \InvalidArgumentException     */    public function addBinding($value, $type = 'where')    {        if (!array_key_exists($type, $this->bindings)) {            throw new InvalidArgumentException("Invalid binding type: {$type}.");        }        if (is_array($value)) {            $this->bindings[$type] = array_values(array_merge($this->bindings[$type], $value));        } else {            $this->bindings[$type][] = $value;        }        return $this;    }    /**     * Merge an array of bindings into our bindings.     *     * @param  \Illuminate\Database\Query\Builder  $query     * @return $this     */    public function mergeBindings(Builder $query)    {        $this->bindings = array_merge_recursive($this->bindings, $query->bindings);        return $this;    }    /**     * Get the database connection instance.     *     * @return \Illuminate\Database\ConnectionInterface     */    public function getConnection()    {        return $this->connection;    }    /**     * Get the database query processor instance.     *     * @return \Illuminate\Database\Query\Processors\Processor     */    public function getProcessor()    {        return $this->processor;    }    /**     * Get the query grammar instance.     *     * @return \Illuminate\Database\Query\Grammars\Grammar     */    public function getGrammar()    {        return $this->grammar;    }    /**     * Use the write pdo for query.     *     * @return $this     */    public function useWritePdo()    {        $this->useWritePdo = true;        return $this;    }    /**     * Handle dynamic method calls into the method.     *     * @param  string  $method     * @param  array   $parameters     * @return mixed     *     * @throws \BadMethodCallException     */    public function __call($method, $parameters)    {        if (Str::startsWith($method, 'where')) {            return $this->dynamicWhere($method, $parameters);        }        $className = get_class($this);        throw new BadMethodCallException("Call to undefined method {$className}::{$method}()");    }}