I am a beginner at SQL. I have a single table called enrolment where I have users (user_id) who can have either single or multiple courses which are represented using course_id. I want to find the users who are only…
I am using SQLAlchemy ORM. I have a Parent class and a Child class. Parent and Child are in a one-to-many relationship. A Parent has many children, potentially even 20k-30k. Here's how my classes are set up class Parent(Base): __tablename__…
I'm working with event sourced data where all of the important fields are combined to a JSONB column and many of the keys are missing from most of the database rows. I would want to get: Aggregated combined values of…
I'm facing a performance issue with a complex SQL query in PostgreSQL and seeking your expertise to help optimize it. The query involves multiple tables and joins and seems to be taking longer to execute than expected. I believe there…
Using Postgresql and Spring. The Backend gets User Input from the frontend which is called "filter". I want the database "contacts" to be checked in multiple columns: @Query("SELECT c FROM Contacts c " + "WHERE LOWER(CAST(c.supplierNo AS string)) LIKE %:filter%…
Column A Column B Column C Column D A B C A D A A B C A D A This is the table for instance. We are supposed to find the number of occurrences of A in the entire…
I have a problem. i need to research through query all text containing a substring given by a post method on php. for example, if i input an "a" or a number like "1" (char not int) i need to…
I have a table master_data_approval_table in my postgres DB having field approval_value (type Jsonb) which contains below structure: We want only those records where each object of jsonb array strictly matches the given condition "status": "Approved" Expected O/P: I tried…
I am trying to retrieve data from public.users tables and this the query I am using but I am not able to retrieve, what i actually require: WITH duplicates AS ( SELECT email, COUNT(*) AS duplicate_count FROM public.users GROUP BY…
I am joining two tables with the student table using the inner join below: select (first_name || ' ' ||last_name) as "Student Name", gender, race from student inner join gender on student.gender_id = gender.gender_id inner join race on student.race_id =…