Lab Sql

Hi i have a SQL which is extremely slow. select case when (value=1) then (select from table where… Read more Case Clause Execution Procedure

I need some help writing/optimizing a query to retrieve the latest version of each row by type and … Read more How To Obtain The Most Recent Row Per Type And Perform Calculations, Depending On The Row Type?

On our SQL SERVER 2008 R2 database we have an COUNTRIES referential table that contains countries. … Read more Does It Worth Switching A Primary Key From The Type Nvarchar To The Type Int?

I've got a table of stock market moving average values, and I'm trying to compare two value… Read more Rownumber() And Partition By Performance Help Wanted

I have the following database schema: table courses: id tutor_id title table course_categories: … Read more How To Get Data From 4 Tables In 1 Sql Query?

I have a table with columns id,filter1,filter2,time,value which contains millions of records. I wan… Read more Postgres Select N Equally Distributed Rows By Time Over Millions Of Records

I have the following psql table. It has roughly 2 billion rows in total. id word lemma … Read more Painfully Slow Postgres Query Using Where On Many Adjacent Rows

PostgreSQL 7.4 (Yep upgrading) So in my WHERE condition I have this AND CASE WHEN 'substri… Read more Cost Of Sort Is Slowing Down My Query