Bug #119139 Unexpected error `Incorrect DECIMAL value: '0' for column '' at row -1`

• Submitted: 13 Oct 7:30
• Modified: 13 Oct 7:37
• Reporter: chi zhang
• Status: Open
• Category: MySQL Server
• Severity: S1 (Critical)
• Version: 9.4.0
• OS: Any
• CPU Architecture: Any

[13 Oct 7:30] chi zhang

Description:
Hi,

The following test case triggers an unexpected error:

```
CREATE TABLE IF NOT EXISTS t0(c0 DECIMAL) ;
INSERT INTO t0(c0) VALUES(1);
CREATE INDEX i0 ON t0(((LEAST("", 1)) > (t0.c0))); -- Incorrect DECIMAL value: '0' for column '' at row -1
```

How to repeat:
```
CREATE TABLE IF NOT EXISTS t0(c0 DECIMAL) ;
INSERT INTO t0(c0) VALUES(1);
CREATE INDEX i0 ON t0(((LEAST("", 1)) > (t0.c0)));
```

[13 Oct 7:37] chi zhang

I find the following DELETE can also trigger this error:
```
CREATE TABLE IF NOT EXISTS t0(c0 DECIMAL);
INSERT INTO t0(c0) VALUES(1);
PREPARE prepare_query FROM 'DELETE LOW_PRIORITY QUICK FROM t0 WHERE (LEAST("", "")) IN (GREATEST(t0.c0, CAST(-1 AS DECIMAL)))';
EXECUTE prepare_query;
```