How to concatenate strings in phalcon php phql? - php

Question

I have the following Phql query:
$persons = Person::query()
->columns([
'id' => 'id',
'name' => 'first_name || last_name'
])
->where("first_name LIKE :searchQuery:")
->orWhere("last_name LIKE :searchQuery:")
->bind(['searchQuery' => $searchQuery . '%'])
->execute();
The database used is an sqlite database.
The query works fine until I include the concatenation operator of sqlite ||
The exception thrown is:
Scanner: Unknown opcode 402
I have tried CONCAT(first_name, last_name), but it throws the exception:
SQLSTATE[HY000]: General error: 1 no such function: CONCAT

Answer 1

Also much better is to use dialect extension:
namespace App/Dialect;
class Sqlite extends \Phalcon\Db\Dialect\Sqlite
{
/**
* Sqlite constructor.
*/
public function __construct()
{
$this->registerCustomFunctions();
}
/**
* Register Custom dialect functions
*/
public function registerCustomFunctions()
{
$customFunctions = [
'CONCAT_WS' => 'ConcatWs',
];
foreach ($customFunctions as $key => $value) {
$className = 'App\\Dialect\\Extensions\\'.$value;
$object = new $className;
$this->registerCustomFunction($key, $object->getFunction());
}
}
}
namespace App/Dialect/Extensions;
class ConcatWs
{
public function getFunction()
{
return function (Dialect $dialect, $expression) {
$sql = '';
$count = count($expression['arguments']);
if (true !== $count >= 2) {
throw new Exception('CONCAT_WS requires 2 or more parameters');
}
if (2 === $count) {
return $this->getSqlExpression($expression['arguments'][1]);
}
$separator = array_shift($expression['arguments']);
--$count;
foreach ($expression['arguments'] as $argument) {
$sql .= $this->getSqlExpression($argument);
if (0 !== --$count) {
$sql .= ' || '.$this->getSqlExpression($separator).' || ';
}
}
return $sql;
};
}
}
And then in your db service:
use App/Dialect/Sqlite as SqliteDialect;
$di->set('db', function() {
return new Sqlite([
// other options, like password etc
'dialectClass' => SqliteDialect::class
]);
});

Answer 2

Sadly this is not supported for sqllite, but you can extend the class and add support for MySQL concat function. Here is a working solution: https://forum.phalconphp.com/discussion/15233/concatenate-columns-using-sqlite
MySQL solution:
->columns([
'id',
'CONCAT_WS("#", id, created_at) AS concatenatedValue',
])
Result
Array
(
[0] => Array
(
[id] => 1
[concatenatedValue] => 1#2017-04-04 12:08:52