This SQL query retrieves all rows from the `claim` table...

This SQL query retrieves all rows from the claim table where there is no corresponding match in the application table based on the claim_id column.

In detail:

1. FROM claim c:

   • Selects all rows from the claim table and assigns it the alias c.

2. LEFT JOIN application a ON c.claim_id = a.claim_id:

   • Performs a LEFT JOIN between the claim table (aliased as c) and the application table (aliased as a) using the condition that the claim_id column in both tables must match.

   • A LEFT JOIN will include all rows from the claim table, even if there is no match in the application table. For rows in claim without a match in application, columns from the application table will contain NULL.

3. WHERE a.claim_id IS NULL:

   • Filters the results to only include rows from the claim table where there is no matching row in the application table (i.e., rows where a.claim_id is NULL). This ensures that we get only the rows from the claim table that do not have a corresponding row in the application table.

Purpose:

This query is used to find all records in the claim table that do not have an associated record in the application table based on the claim_id relationship.