Question : select * from product where productname in (select productname from product where ProductQty = 89) select * from […]
Tag: exists
Best practice between using LEFT JOIN or NOT EXISTS
Question : Is there a best practice between using a LEFT JOIN or a NOT EXISTS format? What is benefit […]
WHERE IN subquery too slow
Question : I have a FULLTEXT search on the database, with the WHERE IN condition which checks that search results […]
EXISTS() vs EXISTS() = TRUE in Postgres
Question : Faced weird behaviour with EXISTS (also applies for NOT EXISTS) generating different execution plans for WHERE EXISTS(…) EXPLAIN […]
Unexpected results from MariaDB IF EXISTS … THEN
Question : I am having unexpected results from MariaDB IF EXISTS… in a stored procedure. I created a minimal example […]
Which Plan is Better? WHERE EXISTS Instead of INNER JOIN
Question : Did a switch to a WHERE EXISTS in temp table (Object13 in the plans) from an INNER JOIN […]
How does SQL Server process DELETE WHERE EXISTS (SELECT 1 FROM TABLE)?
Question : The below is a valid TSQL statement. But I want to understand how SQL Server processes it. DELETE […]
Select only those records that have same multiple values for a particular column if it’s existing?
Question : Below is an example of my pricing_supports table have more than 3 milions rows. There some rows having […]
Exist on table from linked Server giving Error 4104
Question : I am comparing two tables on different Servers and the query I am running looks like this: Select […]
MySQL under what scenario suitable to use WHERE EXISTS
Question : I recently just noticed that WHERE EXISTS can slow down the operation badly. E.g. select SQL_NO_CACHE count(*) as […]