Documentation Home
MySQL 5.7 C API Developer Guide
Download this Manual
PDF (US Ltr) - 1.1Mb
PDF (A4) - 1.1Mb


5.4.43 mysql_list_fields()

MYSQL_RES *
mysql_list_fields(MYSQL *mysql,
                  const char *table,
                  const char *wild)

Description

Note

As of MySQL 5.7.11, mysql_list_fields() is deprecated and is subject to removal in a future version of MySQL. Instead, use mysql_real_query() or mysql_query() to execute a SHOW COLUMNS statement.

Returns an empty result set for which the metadata provides information about the columns in the given table that match the simple regular expression specified by the wild parameter. wild may contain the wildcard characters % or _, or may be a NULL pointer to match all fields. Calling mysql_list_fields() is similar to executing the query SHOW COLUMNS FROM tbl_name [LIKE wild].

It is preferable to use SHOW COLUMNS FROM tbl_name instead of mysql_list_fields().

You must free the result set with mysql_free_result().

Return Values

A MYSQL_RES result set for success. NULL if an error occurred.

Errors

Example

int i;
MYSQL_RES *tbl_cols = mysql_list_fields(mysql, "mytbl", "f%");

unsigned int field_cnt = mysql_num_fields(tbl_cols);
printf("Number of columns: %d\n", field_cnt);

for (i=0; i < field_cnt; ++i)
{
  /* col describes i-th column of the table */
  MYSQL_FIELD *col = mysql_fetch_field_direct(tbl_cols, i);
  printf ("Column %d: %s\n", i, col->name);
}
mysql_free_result(tbl_cols);