SQL101 errors documented

Common SQL Errors and How to Fix Them

Browse all documented SQL errors with detailed explanations, root causes, and step-by-step fixes.

Cannot drop index 'idx_orders_date' because the index is used by a view or a tri

This error occurs when an attempt is made to drop an index that is being used by a view, trigger, or constraint in the d…

SQL Error (1222): The following SQL statement failed to execute: 'ALTER TABLE or

This error occurs when a SQL statement is executed that attempts to modify a table that does not exist, or a column that…

Subquery returned more than 1 value. This is not permitted when the subquery fol

This error occurs when a subquery is used in a way that expects a single value, but the subquery returns multiple values…

The 'query_builder' instance is missing the 'connection' parameter

This error occurs when trying to use the query builder functionality without properly setting up the connection to the d…

SQL Error: Column 'age' not found in table 'users'.

This error occurs when SQL tries to select, insert, update or delete a column that does not exist in the specified table…

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