Bug #76281 possible false positive for "Prepared Statements Not Being Closed"

• Submitted: 12 Mar 2015 9:27
• Modified: 12 Mar 2015 9:38
• Reporter: Daniël van Eeden (OCA)
• Status: Verified
• Category: MySQL Enterprise Monitor: Advisors/Rules
• Severity: S3 (Non-critical)
• Version: 3.0.20
• OS: Any
• CPU Architecture: Any
• Tags: false postive, prepared statements

[12 Mar 2015 9:27] Daniël van Eeden

Description:
This advisor creates a warning in this situation:
Com_stmt_prepare = 2
Com_stmt_close = 1

Expression
(%Com_stmt_prepare% > 1) && ((100 * (%Com_stmt_close% / %Com_stmt_prepare%)) < THRESHOLD) 

Evaluated Expression
(2 > 1) && ((100 * (1 / 2)) < 60)

(3 > 2) && ((100 * (1 / 3)) < 60)

How to repeat:
See description.

Suggested fix:
Make sure Com_stmt_prepare is greater than 2:

(%Com_stmt_prepare% > 2) && ((100 * (%Com_stmt_close% / %Com_stmt_prepare%)) < THRESHOLD)

Alternative: Make sure there are 2 more prepare's than closes:
(%Com_stmt_prepare% > 1) && (%Com_stmt_prepare% > %Com_stmt_close% + 1) && ((100 * (%Com_stmt_close% / %Com_stmt_prepare%)) < THRESHOLD)

[12 Mar 2015 9:38] MySQL Verification Team

Hello Daniël,

Thank you for the report.

Thanks,
Umesh