Bug #66235 MySQL_ResultSet::getString() returns bad value for BIT data

• Submitted: 7 Aug 2012 3:56
• Modified: 2 Feb 2015 16:26
• Reporter: Alfredo Kojima
• Status: Closed
• Category: Connector / C++
• Severity: S3 (Non-critical)
• Version: 1.1.0
• OS: Any
• Assigned to: Hemant Dangi
• CPU Architecture: Any

[7 Aug 2012 3:56] Alfredo Kojima

Description:
getString() on resultset of SELECT max(bit_field) FROM table_with_bit_field will yield wrong result

How to repeat:
As per bug #63457:

1. Create a table with a BIT field:

CREATE TABLE t(b BIT NOT NULL DEFAULT 0);

2. Insert some data into the table:

INSERT INTO t(b) VALUES(1), (0), (1), (1), (0), (0);

3. Perform a SELECT with a MAX aggregation function over the BIT field:

SELECT MAX(b) FROM t;

The result of a getString() on the resultset returns various values that are not 1 or 0.

[23 Apr 2013 21:13] Lawrenty Novitsky

btw, should really getString for bit field return '0' or '1'? what for bit(n>1) fields? ...

[23 Jan 2015 9:22] Hemant Dangi

Conversion in getString() and getInt() from bit to integer can be skipped, in
case of aggregate functions (MAX() here) as they are already returning values
as unsigned binary.
Committed revision 1024 in C/C++ 1.1.6.

[2 Feb 2015 16:26] Paul DuBois

Noted in 1.1.6 changelog.

For queries of the form SELECT MAX(bit_col) FROM table_with_bit_col,
getString() returned an incorrect result.