DocumentationHackReferenceClassAsyncMysqlRowBlockfieldsCount

AsyncMysqlRowBlock::fieldsCount

Returns the number of fields (columns) associated with the current row block

public function fieldsCount(): int;

Returns

int - The number of columns in the current row block.

Examples

The following example shows how to use AsyncMysqlRowBlock::fieldsCount to get the total number of fields represented in the row block

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 the example, given the table created with the SQL above, there are 4 fields.

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->count() > 0) {
    // An AsyncMysqlRowBlock
    $row_block = $row_blocks[0];
    return $row_block->fieldsCount(); // int
  } else {
    return -1;
  }
}

<<__EntryPoint>>
async function run(): Awaitable<void> {
  $r = await simple_query();
  \var_dump($r);
}
```.hhvm.expectf
int(%d)
```.example.hhvm.out
int(4)
```.skipif
await \Hack\UserDocumentation\API\Examples\AsyncMysql\skipif_async();