Name

OVERLAY

Synopsis

The OVERYLAY function embeds one string into another and returns the result.

SQL2003 Syntax

OVERLAY(string PLACING embedded_string FROM start[FOR length])

If any of the inputs are NULL, the OVERLAY function returns a NULL. The embedded_string replaces the length characters in string starting at character position start. If the length is not specified, then the embedded_string will replace all characters after start in string.

DB2, MySQL, Oracle, and SQL Server

These platforms do not have support for the OVERLAY function. You can simulate the OVERLAY function on these platforms by using a combination of SUBSTRING and the concatenation operator.

PostgreSQL

PostgreSQL supports the ANSI standard for OVERLAY.

Examples

This is an example of how to use the OVERLAY function:

/* SQL2003 and PostgreSQL */
SELECT OVERLAY('DONALD DUCK' PLACING 'TRUMP' FROM 8) FROM NAMES;'DONALD TRUMP'

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