List data present in table1 but not in table2 in MySQL

Guide on writing a MySQL query to list data that is only in table1 and not in table2. This SQL command helps in finding records that do not match between two tables based on a foreign key relationship.

SELECT t1.id, t1.date
FROM table1 t1
LEFT JOIN table2 t2 ON t1.id = t2.table1_id
WHERE t2.table1_id IS NULL;

Detailed explanation:

1. LEFT JOIN: Combines table1 with table2 based on the condition t1.id = t2.table1_id. LEFT JOIN ensures that all rows from table1 are kept, regardless of whether there is a match in table2.

2. WHERE t2.table1_id IS NULL: Filters rows that do not have a corresponding entry in table2. This means only rows from table1 that do not have a match in table2 are returned.

MySQL Version:

This SQL query works on MySQL versions from 5.0 and above, as basic operations like LEFT JOIN and IS NULL conditions are supported in these versions.