Lab Sql

I need help in optimize a PostgreSQL query which uses the BETWEEN clause with a timestamp field. I … Read more Optimize Between Date Statement

In PostgreSQL, I have an index on a date field on my tickets table. When I compare the field agains… Read more Efficient Postgresql Query On Timestamp Using Index Or Bitmap Index Scan?

I have a table bsort: CREATE TABLE bsort(a int, data text); Here data may be incomplete. In other … Read more How Does Postgresql Perform Order By With A B-tree Index On The Field?

I have a large table: CREATE TABLE 'orders' ( 'id' serial NOT NULL, 'person_id&… Read more Optimize Performance For Queries On Recent Rows Of A Large Table

This is a follow-up to this question, where my query was improved to use window functions instead o… Read more Window Functions Filter Through Current Row

This question is about the functionality of first_value(), using another function or workaround. It… Read more Best Performance In Sampling Repeated Value From A Grouped Column

I have a star schema here and I am querying the fact table and would like to join one very small di… Read more Why Does The Following Join Increase The Query Time Significantly?