The difference between and and or in sql
The difference between AND and OR in SQL: When AND connects Boolean expressions, it requires all conditions to be met before it returns True, narrowing the query results. When OR connects Boolean expressions, it requires that any condition is met and True is returned to expand the query results.
The difference between AND and OR in SQL
In SQL, AND and OR are logical operators, used Used to join Boolean expressions and form more complex query conditions. The main difference between them is the number of records in the query results.
AND
- Concatenate multiple Boolean expressions to form a new Boolean expression that only occurs when all connected expressions are equal It is true only when it is true.
- Using AND can narrow the query results because it only returns records that meet all conditions at the same time.
For example:
<code>SELECT * FROM table_name WHERE column1 = 'value1' AND column2 = 'value2';</code>
This query will return all items that satisfy both the conditions column1 is equal to 'value1' and column2 is equal to 'value2' Record.
OR
- Connect multiple Boolean expressions to form a new Boolean expression. This expression will be used when any connected expression is true when true.
- Using OR can expand query results because it returns records that meet any condition.
For example:
<code>SELECT * FROM table_name WHERE column1 = 'value1' OR column2 = 'value2';</code>
This query will return all records that meet the condition of column1 is equal to 'value1' or column2 is equal to 'value2' .
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