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Using a SELECT statement after the INSERT statement with a database-specific function that returns the generated primary key for the most recently inserted row. For example, LAST_INSERT_ID() for MySQL. Using a unique combination of elements from the original SQL INSERT in a subsequent SELECT statement.
There is also an IGNORE clause for the INSERT statement, [7] which tells the server to ignore "duplicate key" errors and go on (existing rows will not be inserted or updated, but all new rows will be inserted). SQLite's INSERT OR REPLACE INTO works similarly. It also supports REPLACE INTO as an alias for compatibility with MySQL. [8]
A prepared statement takes the form of a pre-compiled template into which constant values are substituted during each execution, and typically use SQL DML statements such as INSERT, SELECT, or UPDATE. A common workflow for prepared statements is: Prepare: The application creates the statement template and sends it to the DBMS.
A query includes a list of columns to include in the final result, normally immediately following the SELECT keyword. An asterisk ("*") can be used to specify that the query should return all columns of the queried tables. SELECT is the most complex statement in SQL, with optional keywords and clauses that include:
SELECT is the most common operation in SQL, called "the query". SELECT retrieves data from one or more tables, or expressions. Standard SELECT statements have no persistent effects on the database. Some non-standard implementations of SELECT can have persistent effects, such as the SELECT INTO syntax provided in some databases. [4]
In SQL:1999 a recursive (CTE) query may appear anywhere a query is allowed. It's possible, for example, to name the result using CREATE [ RECURSIVE ] VIEW . [ 16 ] Using a CTE inside an INSERT INTO , one can populate a table with data generated from a recursive query; random data generation is possible using this technique without using any ...
Suppose you have a trigger that is called on an INSERT to a certain table. If your trigger is using the BEFORE option, the code within the trigger will be executed before the INSERT into the table occurs. A common use of the BEFORE trigger is to verify the input values of the INSERT, or modify the values accordingly.
In SQL, the data manipulation language comprises the SQL-data change statements, [3] which modify stored data but not the schema or database objects. Manipulation of persistent database objects, e.g., tables or stored procedures, via the SQL schema statements, [3] rather than the data stored within them, is considered to be part of a separate data definition language (DDL).