Change mysql error detection strategy
Change mysql error detection strategy

Previous to this commit, some mysql connection errors were not detected
by the client.

This commit changes from implicit error detection via checking
mysql_field_count() to explicit detection via mysql_errno().

http://dev.mysql.com/doc/refman/5.0/en/null-mysql-store-result.html

jeremy/mysql2,zmack/mysql2,zBMNForks/mysql2,yui-knk/mysql2,kamipo/mysql2,bigcartel/mysql2,modulexcite/mysql2,coupa/mysql2,coupa/mysql2,blaind/mysql2,brianmario/mysql2,zmack/mysql2,marshall-lee/mysql2,marshall-lee/mysql2,brianmario/mysql2,PipelineDeals/mysql2,jeremy/mysql2,PipelineDeals/mysql2,yui-knk/mysql2,mkdynamic/mysql2,mkdynamic/mysql2,zBMNForks/mysql2,kamipo/mysql2,sodabrew/mysql2,bloopletech/mysql2,mkdynamic/mysql2,modulexcite/mysql2,modulexcite/mysql2,mkdynamic/mysql2,webdev1001/mysql2,tamird/mysql2,kamipo/mysql2,jeremy/mysql2,yui-knk/mysql2,bigcartel/mysql2,PipelineDeals/mysql2,webdev1001/mysql2,tamird/mysql2,jconroy77/mysql2,webdev1001/mysql2,zBMNForks/mysql2,marshall-lee/mysql2,tamird/mysql2,blaind/mysql2,zmack/mysql2,kamipo/mysql2,brianmario/mysql2,jconroy77/mysql2,bigcartel/mysql2,dylanahsmith/mysql2,jconroy77/mysql2,PipelineDeals/mysql2,tamird/mysql2,zmack/mysql2,yui-knk/mysql2,dylanahsmith/mysql2,bigcartel/mysql2,zBMNForks/mysql2,sodabrew/mysql2,marshall-lee/mysql2,webdev1001/mysql2,bloopletech/mysql2,sodabrew/mysql2,jconroy77/mysql2,modulexcite/mysql2