Bug #38852 FLOAT(M,D) description in manual different to actual behaviour

• Submitted: 18 Aug 2008 12:51
• Modified: 18 Aug 2008 15:40
• Reporter: Thomas Tallyce
• Status: Not a Bug
• Category: MySQL Server
• Severity: S3 (Non-critical)
• Version: 5.0.51a-community
• OS: Linux (SUSE)
• CPU Architecture: Any

[18 Aug 2008 12:51] Thomas Tallyce

Description:
http://dev.mysql.com/doc/refman/5.1/en/numeric-types.html
says:

"MySQL allows a non-standard syntax: FLOAT(M,D)  or REAL(M,D)  or DOUBLE PRECISION(M,D). Here, “(M,D)” means than values can be stored with up to M digits in total, of which D digits may be after the decimal point.

I read this to mean that a FLOAT(5,2) field should accept and store unmodified the following example values:

123.45
1234.5
12345

The latter two cases, however, result in rounding:

123.45
999.99
999.99

So I think the documentation is wrong, or MySQL is not correctly accepting the value.

How to repeat:
See description

[18 Aug 2008 15:39] Paul DuBois

"up to M digits in total, of which D digits may be after the decimal point" means that up to M-D digits may precede the decimal point. These two values do not fit that description:

1234.5
12345