Error
Error Code:
1090
MySQL Error 1090: Cannot Delete All Columns
Description
MySQL Error 1090 occurs when an `ALTER TABLE` statement attempts to remove all columns from a table. MySQL prevents this operation because a table must always contain at least one column to maintain its structural definition. This error indicates that the `ALTER TABLE` command is being misused for what should be a table deletion operation.
Error Message
You can't delete all columns with ALTER TABLE; use DROP TABLE instead
Known Causes
3 known causesAttempting to Remove Last Column
The `ALTER TABLE DROP COLUMN` statement targets the very last column remaining in the table, which MySQL disallows as a table must retain at least one column.
Misunderstanding ALTER TABLE Scope
The user's query incorrectly uses `ALTER TABLE` with the intent to effectively delete the entire table structure, rather than modify its existing columns.
Flawed Script Logic
An automated script or complex query inadvertently generates an `ALTER TABLE` statement that attempts to drop all columns from a table.
Solutions
Coming SoonDetailed step-by-step solutions for this error are being prepared. In the meantime, try these general troubleshooting tips:
General Troubleshooting Tips
- Check the error message carefully for specific details
- Review recent changes that might have caused the error
- Search for the exact error code in the official documentation
- Check log files for additional context
- Try restarting the application or service