Fetch a single column from a result set of a query. The function takes care of doing the query and freeing the results when finished.
the SQL query or the statement to prepare
which column to return (integer [column number, starting at 0] or string [column name])
array, string or numeric data to be added to the prepared statement. Quantity of items passed must match quantity of placeholders in the prepared statement: meaning 1 placeholder for non-array parameters or 1 placeholder per array element.
If supplied, prepare()/ execute() is used.
Table 21-1. Possible PEAR_Error values
| Error code | Error message | Reason | Solution |
|---|---|---|---|
| DB_ERROR_INVALID | NULL | SQL statment for preparing is not valid. | See the prepare() documentation, if you want to use a SQL statemt using placeholders. |
| DB_ERROR_MISMATCH | NULL | Quantity of parameters didn't match quantity of placeholders in the prepared statment. | Check that the number of placeholders in the prepare() statement passed to $query equals the count of entries passed to $params. |
| DB_ERROR_NODBSELECTED | NULL | No database was choosen. | Check the DSN in connect(). |
| DB_ERROR_TRUNCATED | NULL | The result set contains fewer then two columns | Check the SQL query or choose another get*() function |
| every other error code | Database specific error | Check the database related section of PHP-Manual to detect the reason for this error. In the most cases a misformed SQL statment. Ie. using LIMIT in a SQL-Statment for an Oracle database. |