Which command is used for data retrieval in sql
The command used for data retrieval in SQL is the SELECT command, which allows the user to select specific data from a table. Syntax: SELECT column1, column2, ..., columnN FROM table_name [WHERE condition] [ORDER BY column_name [ASC | DESC]] [LIMIT row_count].
Commands used for data retrieval in SQL
The SELECT command is the basic command used for data retrieval in SQL . It allows users to select specific rows and columns of data from a database table.
Syntax
<code>SELECT column1, column2, ..., columnN FROM table_name [WHERE condition] [ORDER BY column_name [ASC | DESC]] [LIMIT row_count]</code>
Parameters
- ##column1, column2, ..., columnN:The column name to be retrieved.
- table_name: The name of the table to retrieve data.
- WHERE condition: (Optional) Condition for retrieving specific row data.
- ORDER BY column_name: (Optional) Sorts results based on a specific column. You can specify ASC
(ascending order) orDESC(descending order). - LIMIT row_count: (Optional) Limit the number of rows retrieved.
Example
<code>SELECT name, email FROM customers WHERE city = 'London' ORDER BY name ASC LIMIT 10;</code>This query will select the names and email addresses of all London customers from a table called "customers", sorted by name in ascending order Sort the results and retrieve only the first 10 records.
Other Notes
- The SELECT command can retrieve data from a single table or multiple tables.
- You can use the wildcard character
- *
to retrieve data for all columns, such asSELECT * FROM table_name;. Aggregation functions (such as - SUM()
,COUNT(),AVG()) can be used to summarize data.
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