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IF EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'X' AND COLUMN_NAME = 'Y') IF EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'Z' AND COLUMN_NAME = 'A') BEGIN UPDATE [dbo].[X] SET Y= (SELECT inst.[A] FROM [dbo].[Z] s WHERE s.[B] = [dbo].[x].[B]); END GO I want to combine the 2 IF confitions and perform the update only when both of them are satisfied. Is there some way in which I can club 2 IF EXISTS?
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Key differences between IN and EXISTS OperatorThe IN clause scan all records fetched from the given subquery column, whereas EXISTS clause evaluates true or false, and the SQL engine quits the scanning process as soon as it found a match.
It works fine if the object exists in the database. In case the object does not exist, and you try to drop, you get the following error. To avoid this situation, usually, developers add T-SQL If Exists statement and drop the object if it is already available in the database.
Using EXISTS clause in the CASE statement to check the existence of a record. Using EXISTS clause in the WHERE clause to check the existence of a record. EXISTS clause having subquery joining multiple tables to check the record existence in multiple tables.
To test whether a row exists in a MySQL table or not, use exists condition. The exists condition can be used with subquery. It returns true when row exists in the table, otherwise false is returned. True is represented in the form of 1 and false is represented as 0.
Simple:
IF EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'X' AND COLUMN_NAME = 'Y') AND EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'Z' AND COLUMN_NAME = 'A') BEGIN UPDATE [dbo].[X] SET Y= (SELECT inst.[A] FROM [dbo].[Z] s WHERE s.[B] = [dbo].[x].[B]); END GO If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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