We have alot of tables where we have implemented a column 'SearchColumn' which takes all varchar fields in the table and concatinates them. In our application we use this field only this way: SELECT [field1], [field2], [field3] FROM MyTable WHERE [SearchColumn] LIKE '%value%';
Meaning it needs to perform a table scan everytime.All best practices/ articles sais that persisted computed columns is faster than non-persisted computed columns. However our tests haven't showed any significant differences. Other than persisted takes alot more space on disk.So when doing a [ComputedColumn] LIKE '%value%'
where it contains a wildcard both infront and at the end it actually is better to choose non-persisted ?
Performance: Persisted comp. cols vs non-pers.c.c.
Posted - 2008-07-04 : 04:46:03
