fieldType

Note

This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information.

Returns the type of the field (column)

public function fieldType(
  mixed $field,
): int;

See here and here for the integer mappings to SQL types.

Parameters

• mixed $field - the field index (int) or field name (string).

Returns

• int - The type of the field as an int.

Examples

The following example shows how to use AsyncMysqlRow::fieldType to get the data type of the email field. Here are the available data types:

Type Value	Type Description	Int Value
MYSQL_TYPE_DECIMAL	DECIMAL or NUMERIC field	0
MYSQL_TYPE_TINY	TINYINT field	1
MYSQL_TYPE_SHORT	SMALLINT field	2
MYSQL_TYPE_LONG	INTEGER field	3
MYSQL_TYPE_FLOAT	FLOAT field	4
MYSQL_TYPE_DOUBLE	DOUBLE or REAL field	5
MYSQL_TYPE_NULL	NULL-type field	6
MYSQL_TYPE_TIMESTAMP	TIMESTAMP field	7
MYSQL_TYPE_LONGLONG	BIGINT field	8
MYSQL_TYPE_INT24	MEDIUMINT field	9
MYSQL_TYPE_DATE	DATE field	10
MYSQL_TYPE_TIME	TIME field	11
MYSQL_TYPE_DATETIME	DATETIME field	12
MYSQL_TYPE_YEAR	YEAR field	13
MYSQL_TYPE_BIT	BIT field (MySQL 5.0.3 and up)	16
MYSQL_TYPE_NEWDECIMAL	Precision math DECIMAL or NUMERIC field (MySQL 5.0.3 and up)	246
MYSQL_TYPE_ENUM	ENUM field	247
MYSQL_TYPE_SET	SET field	248
MYSQL_TYPE_BLOB	BLOB or TEXT field (use max_length to determine the maximum length)	252
MYSQL_TYPE_VAR_STRING	VARCHAR or VARBINARY field	253
MYSQL_TYPE_STRING	CHAR or BINARY field	254
MYSQL_TYPE_GEOMETRY	Spatial field	255

See: http://mflib.org/mysql/include/mysql_com.h and https://dev.mysql.com/doc/refman/5.0/en/c-api-data-structures.html.

This is an example of what could have been used to create the table from where we are getting our field flags

CREATE TABLE test_table (
userID SMALLINT UNSIGNED ZEROFILL NOT NULL AUTO_INCREMENT,
name VARCHAR(40) NOT NULL,
age SMALLINT NULL,
email VARCHAR(60) NULL,
PRIMARY KEY (userID)
);

So, in our example, 253 would be returned for the email field.

use \Hack\UserDocumentation\API\Examples\AsyncMysql\ConnectionInfo as CI;

async function connect(
  \AsyncMysqlConnectionPool $pool,
): Awaitable<\AsyncMysqlConnection> {
  return await $pool->connect(
    CI::$host,
    CI::$port,
    CI::$db,
    CI::$user,
    CI::$passwd,
  );
}
async function simple_query(): Awaitable<int> {
  $pool = new \AsyncMysqlConnectionPool(darray[]);
  $conn = await connect($pool);
  $result = await $conn->query('SELECT * FROM test_table WHERE userID < 50');
  $conn->close();
  // A call to $result->rowBlocks() actually pops the first element of the
  // row block Vector. So the call actually mutates the Vector.
  $row_blocks = $result->rowBlocks();
  if (!$row_blocks->isEmpty()) {
    // An AsyncMysqlRowBlock
    $row_block = $row_blocks[0];
    if (!$row_block->isEmpty()) {
      // An AsyncMysqlRow
      $row = $row_block->getRow(0);
      return $row->fieldType('email'); // int
    }
    return -1;
  } else {
    return -1;
  }
}

<<__EntryPoint>>
async function run(): Awaitable<void> {
  $r = await simple_query();
  \var_dump($r);
}
```.hhvm.expectf
int(%d)
```.example.hhvm.out
int(253)
```.skipif
await \Hack\UserDocumentation\API\Examples\AsyncMysql\skipif_async();