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David 2 1 avatar image
David 2 1 asked

Improving Performance on Computed Column?

Hi there, What is the best method to improve the query performance on a computed column? For example I have a simple table with ~16,000 rows however when I remove the following computed column from the query it returns the results in half the time: CREATE TABLE TEST_TBL( ID INT IDENTITY (1,1) NOT NULL, DATA_ZIP VARBINARY(MAX), DATA_JSON VARBINARY(MAX), JSON AS (CONVERT(NVARCHAR(MAX),DATA_JSON)) ) I'm struggling to improve performance on this table. TIA
tsqlperformancecomputed-column
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anthony.green answered
Try changing the computed column to persisted, that will force the conversion to be stored in the table, rather than having to convert it on the fly with each select.
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Thanks for confirming.
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