Updated on 2024-06-03 GMT+08:00

PREPARE

Description

Creates a prepared statement.

A prepared statement is a performance optimizing object on the server. When the PREPARE statement is executed, the specified query is parsed, analyzed, and rewritten. When EXECUTE is executed, the prepared statement is planned and executed. This avoids repetitive parsing and analysis. After the PREPARE statement is created, it exists throughout the database session. Once it is created (even if in a transaction block), it will not be deleted when a transaction is rolled back. It can only be deleted by explicitly calling DEALLOCATE or automatically deleted when the session ends.

Syntax

PREPARE name [ ( data_type [, ...] ) ] AS statement;

Parameters

  • name

    Specifies the name of a prepared statement. It must be unique in the session.

  • data_type

    Specifies the type of an argument.

  • statement

    Specifies a SELECT, INSERT, UPDATE, DELETE, MERGE INTO, or VALUES statement.

Examples

See Examples in section "EXECUTE."

Helpful Links

DEALLOCATE and 7.13.10.1-EXECUTE