MYSQL_FIELD *mysql_fetch_field(MYSQL_RES
*result)
Description
Returns the definition of one column of a result set as a
MYSQL_FIELD structure. Call this function
repeatedly to retrieve information about all columns in the
result set. mysql_fetch_field()
returns NULL when no more fields are left.
mysql_fetch_field() is reset to
return information about the first field each time you execute a
new SELECT query. The field
returned by mysql_fetch_field()
is also affected by calls to
mysql_field_seek().
If you've called mysql_query()
to perform a SELECT on a table
but have not called
mysql_store_result(), MySQL
returns the default blob length (8KB) if you call
mysql_fetch_field() to ask for
the length of a BLOB field. (The
8KB size is chosen because MySQL doesn't know the maximum length
for the BLOB. This should be made
configurable sometime.) Once you've retrieved the result set,
field->max_length contains the length of
the largest value for this column in the specific query.
Return Values
The MYSQL_FIELD structure for the current
column. NULL if no columns are left.
Errors
None.
Example
MYSQL_FIELD *field;
while((field = mysql_fetch_field(result)))
{
printf("field name %s\n", field->name);
}