I want to change the type of a column in MS SQL Server 2005, but before开发者_开发技巧 i change the type of that column i want to check if that column is of the type i want to change. How can i do that in SQL?
Thanxs, Bas Hendriks.
Based on the anwser i wrote the following query that did the trick:
IF NOT EXISTS (SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'e_application'
AND COLUMN_NAME = 'txt_locked_by'
AND DATA_TYPE = 'nvarchar'
AND CHARACTER_MAXIMUM_LENGTH = 15 )
BEGIN
ALTER TABLE.....
END
You can query the INFORMATION_SCHEMA
tables.
E.g.
SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'MyTable'
you can use sp_help TableName
, it also retrieve's the column's data types and other properties
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