Difference between revisions of "OpenDBX/C API/odbx column count"
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odbx_result_t* '''result''' ) | odbx_result_t* '''result''' ) | ||
| − | = Description | + | = Description = |
| − | Returns the number of columns | + | Returns the number of columns which belongs to the current result set allocated by [[OpenDBX result|odbx_result()]]. The number won't change within a result set with one notable exception: MySQL returns all outstanding rows of a previous result set first if they were not fetched completely by [[OpenDBX row_fetch|odbx_row_fetch()]] before. Therefore, the column count might change in this special situation. It is strongly advised to fetch all rows of a result set before calling [[OpenDBX result|odbx_result()]] again because other backends will return an error in this case. |
| − | + | The '''result''' parameter required by this function must be a valid result set returned by [[OpenDBX result|odbx_result()]] and must not have been feed to [[OpenDBX result_free|odbx_result_free()]] before. | |
| − | + | = Return values = | |
| − | + | '''opendbx_column_count()''' returns the number of columns/fields which are available in the current result set. The value depend on the column list being part of the SELECT query and it is zero if the query wasn't a SELECT-like query. | |
| − | + | = Errors = | |
| − | + | This function will also return zero if the '''result''' parameter is invalid. | |
| − | + | = See also = | |
| − | + | * [[OpenDBX column_name|odbx_column_name()]] | |
| − | + | * [[OpenDBX column_type|odbx_column_type()]] | |
| − | * [[ | + | |
| − | * [[ | + | |
---- | ---- | ||
Back to [[OpenDBX API|Overview]] | Back to [[OpenDBX API|Overview]] | ||
Revision as of 21:25, 24 April 2007
#include <odbx.h>
unsigned long odbx_column_count(
odbx_result_t* result )
Description
Returns the number of columns which belongs to the current result set allocated by odbx_result(). The number won't change within a result set with one notable exception: MySQL returns all outstanding rows of a previous result set first if they were not fetched completely by odbx_row_fetch() before. Therefore, the column count might change in this special situation. It is strongly advised to fetch all rows of a result set before calling odbx_result() again because other backends will return an error in this case.
The result parameter required by this function must be a valid result set returned by odbx_result() and must not have been feed to odbx_result_free() before.
Return values
opendbx_column_count() returns the number of columns/fields which are available in the current result set. The value depend on the column list being part of the SELECT query and it is zero if the query wasn't a SELECT-like query.
Errors
This function will also return zero if the result parameter is invalid.
See also
Back to Overview
