# cubrid_is_instance

(PECL CUBRID >= 8.3.0)

cubrid_is_instance — Check whether the instance pointed by OID exists

### 说明

cubrid_is_instance ( resource `$conn_identifier` , string `$oid` ) : int

The cubrid_is_instance() function is used to check whether the instance pointed by the given `oid` exists or not.

### 参数

`conn_identifier`

  Connection identifier.

`oid`

  OID of the instance that you want to check the existence.

### 返回值

1, if such instance exists;

0, if such instance does not exist;

-1, in case of error

### 范例

Example #1 cubrid_is_instance() example

    <?php
    $conn = cubrid_connect("localhost", 33000, "demodb");

    $sql = <<<EOD
    SELECT host_year, medal, game_date
    FROM game
    WHERE athlete_code IN
        (SELECT code FROM athlete WHERE name='Thorpe Ian');
    EOD;

    $req = cubrid_execute($conn, $sql, CUBRID_INCLUDE_OID);
    $oid = cubrid_current_oid($req);

    $res = cubrid_is_instance ($conn, $oid);
    if ($res == 1) {
        echo "Instance pointed by $oid exists.\n";
    } else if ($res == 0){
        echo "Instance pointed by $oid doesn't exist.\n";
    } else {
        echo "error\n";
    }

    cubrid_disconnect($conn);
    ?>

以上例程会输出：

    Instance pointed by @0|0|0 doesn't exist.

### 参见

- cubrid_drop() - Delete an instance using OID
- cubrid_get_class_name() - Get the class name using OID