I am writing some knex queries to check if a supplied code otherwise known as a voucher is legitimate under 4 constraints. The voucher exists The voucher has not expired The voucher is for the …
How subquery works?
My understanding of the logical order of execution of sql query is that FROM which gives us the base set of data WHERE which filters the base set data SELECT returning the filtered data I am not able to wrap my head around in the working of this query which contains a subquery:- I mean here, when WHERE is fil…
MySQL – Select where first character is lowercase or uppercase
Sorry if this is something that was asked before, but I am not able to find the answer to this. How do I create a MySQL select statement to select all strings from the database whose first characters …
Calculate rank of the users based on their max score using mysql
I have a table (called users) I need rank of users based on their score but I want rank on the bases of users max score. Expect result Answer You are looking for DENSE_RANK, But it supports mysql version higher than 8.0 use correlated-subquery to get max value by each User_id use two variables one to store ra…
How to look if the value reoccurs in the table after current selection in SQL
I have below data table [CRA_feasibility_test] atmid CRA monday tuesday wednesday thursday friday saturday DA0068C1 ABC Y N Y N N Y I …
Postgres – Multiple conditions on single column with the WHERE AND condition?
So I have a query as follows: SELECT AVG(ratings.rating) FROM ratings INNER JOIN movies ON movies.movieid = ratings.movieid INNER JOIN hasagenre ON hasagenre.movieid = movies.movieid INNER JOIN …
Why is MySQL SUM query only returning one row?
I am trying to create a MySQL query to return the sum of all statement balances for each account in my DB. The query looks like this: SELECT SUM(balance), handle FROM statement_versions INNER JOIN …
Postgresql – Return a column resulting from join as single json column
I have a many to many relationship between users and roles table (A typical usecase). They are related together using a user_role table. I execute the below query: select u.id, u.first_name, u….
Yesterday SQL Server
I know very little SQL and have been asked to fix a problem in existing code. The code is PHP but the SQL causing the problem is: $sql = “INSERT INTO Intranet.dbo.DailyBilling (Date, JobCode, SubJob,…
Select Subquery Group By
I am having an issue with this simple query. I get the error “Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, , >= or when the subquery is …