SqlHelper::getLengthFunction

public function getLengthFunction($field);

/**
 * Returns function for converting string value into datetime.
 * $value must be in YYYY-MM-DD HH:MI:SS format.
 * 

 * $value parameter is SQL unsafe.
 *
 * @param string $value String in YYYY-MM-DD HH:MI:SS format.
 *
 * @return string
 * @see SqlHelper::formatDate
 */
abstract public function getCharToDateFunction($value);

/**
 * Returns function for converting database field or expression into string.
 * 

 * Result string will be in YYYY-MM-DD HH:MI:SS format.
 * 

 * $fieldName parameter is SQL unsafe.
 *
 * @param string $fieldName Database field or expression.
 *
 * @return string
 * @see SqlHelper::formatDate
 */
abstract public function getDateToCharFunction($fieldName);

/**
 * Returns CAST expression for converting field or expression into string
 *
 * @param string $fieldName
 *
 * @return string
 */
abstract public function castToChar($fieldName);

/**
 * Returns expression for text field being used in group or order
 * @see BitrixMainORMQueryQuery::buildGroup
 * @see BitrixMainORMQueryQuery::buildOrder
 *
 * @param string $fieldName
 *
 * @return string
 */
abstract public function softCastTextToChar($fieldName);

/**
 * Transforms Sql according to $limit and $offset limitations.
 * 

 * You must specify $limit when $offset is set.
 *
 * @param string $sql Sql text.
 * @param integer $limit Maximum number of rows to return.
 * @param integer $offset Offset of the first row to return, starting from 0.
 *
 * @return string
 * @throws MainArgumentException
 */
abstract public function getTopSql($sql, $limit, $offset = 0);

/**
 * Builds the strings for the SQL INSERT command for the given table.
 *
 * @param string $tableName A table name.
 * @param array  $fields    Array("column" => $value)[].
 *
 * @param bool   $returnAsArray
 *
 * @return array (columnList, valueList, binds)
 */
public function prepareInsert($tableName, array $fields, $returnAsArray = false)
{
	$columns = array();
	$values = array();

	$tableFields = $this->connection->getTableFields($tableName);

	// one registry
	$tableFields = array_change_key_case($tableFields, CASE_UPPER);
	$fields = array_change_key_case($fields, CASE_UPPER);

	foreach ($fields as $columnName => $value)
	{
		if (isset($tableFields[$columnName]))
		{
			$columns[] = $this->quote($columnName);
			$values[] = $this->convertToDb($value, $tableFields[$columnName]);
		}
		else
		{
			trigger_error("Column `{$columnName}` is not found in the `{$tableName}` table", E_USER_WARNING);
		}
	}

	$binds = $this->prepareBinds($tableFields, $fields);

	return array(
		$returnAsArray ? $columns : implode(", ", $columns),
		$returnAsArray ? $values : implode(", ", $values),
		$binds
	);
}