COLUMNEXISTS()
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Contents
Purpose
Function to check whether a specific column exists
Syntax
COLUMNEXISTS(<expC1>, <expC2>, <expC3> [, <expN1> [, <expN2>]])
See Also
CLOSE DATABASES, CREATE DATABASE, DATABASE(), DATABASEEXISTS(), DBC(), DBF(), FILE(), OPEN DATABASE, TABLEEXISTS(), USE, USED()
Description
The COLUMNEXISTS() function returns .T. if the specified column exists and .F. otherwise.
Parameters | Required | Description |
---|---|---|
<expC1> | Yes | Database name |
<expC2> | Yes | Table name |
<expC3> | Yes | Column name |
<expN1> | No | Column width |
<expN2> | No | Column decimal places |
Example
if columnexists("southwind","customers","customerid",5,0) open database southwind use customers else open database southwind alter table customers (...) endif