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Can anyone comment on the performance of the following select statement
when most of the rows in the table will contain NULL values for the
"hobbies" varchar2(1024) column.
The "hobbies" will be a string with the following format
"football:hockey:cricket..."
I already know that this type of search is slow since Oracle needs to
scan the string completely. Since most rows are NULL, will Oracle still
walk thru each row ? Is it worth indexing the someinfo column, to stop
Oracle from checking rows containing Nulls ?
THanks,
Bill
SELECT name from employee
where
hobbies like '%football%'
Received on Thu Jun 17 1999 - 13:21:17 CDT