MySQL Bugs: #99707: EXPLAIN requires more than SELECT

Bug #99707	EXPLAIN requires more than SELECT
Submitted:	27 May 2020 12:33	Modified:	1 Jun 2020 11:42
Reporter:	Francisco Miguel Biete Banon	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Documentation	Severity:	S3 (Non-critical)
Version:	8.0.20, 5.7.30	OS:	Any
Assigned to:		CPU Architecture:	Any
Tags:	explain, privileges

Description:
EXPLAIN documentation is incorrect:

From v8 documentation
```
EXPLAIN requires the SELECT privilege for any tables or views accessed, including any underlying tables of views. For views, EXPLAIN also requires the SHOW VIEW privilege. EXPLAIN ... FOR CONNECTION additionally requires the PROCESS privilege if the specified connection belongs to a different user.
```

https://dev.mysql.com/doc/refman/8.0/en/explain.html

That's not correct.

EXPLAIN requires the same privileges that the operation trying to explain would require. For example, running EXPLAIN for a DELETE would require DELETE...

How to repeat:
Try to EXPLAIN INSERT/UPDATE/DELETE with an account with SELECT only

Suggested fix:
If the documentation is correct, then SELECT should be enough to explain INSERT/DELETE/UPDATE...

If the documentation is not correct, then it should be updated.

Hi Mr. Banon,

Thank you for your documentation enhancement request.

I think that your analysis is correct.

Verified as reported.

Posted by developer:
 
Revised to:

EXPLAIN requires the same privileges required to execute the explained statement. Additionally, EXPLAIN also requires the SHOW VIEW privilege for any explained view. EXPLAIN ... FOR CONNECTION also requires the PROCESS privilege if the specified connection belongs to a different user.

Thank you, Paul.