How to Fix “Unknown column ‘CONCAT'” in Laravel

The laravel unknown column ‘CONCAT’ error appears the moment you try to use a SQL function like CONCAT() directly inside ->select(). Laravel’s query builder escapes every string argument as an identifier by default, so your SQL expression gets wrapped in backticks and shipped to MySQL as a column name that obviously doesn’t exist. The fix is to tell Eloquent “this is raw SQL, don’t touch it” — via DB::raw() or selectRaw(). This guide covers both, when to pick which, and the accessor-vs-SQL trade-off that comes up next.

Last verified: 2026-04-23 on Laravel 11 with PHP 8.3 and MySQL 8.0. Originally published 2022-11-06, rewritten and updated 2026-04-23.

TL;DR

Wrap the SQL expression in DB::raw() — or switch the call to selectRaw(). Both stop Laravel from escaping the expression as a column name, which is what produces the “Unknown column ‘CONCAT…'” error.

Why the error happens

When you pass strings to ->select(), the query builder treats each one as a column identifier. It wraps them in backticks (MySQL) or double quotes (PostgreSQL), which is what keeps reserved words and mixed-case column names working. But that same escaping turns an unescaped SQL expression into a single malformed identifier:

// Eloquent call
User::where('id', '=', 10)
    ->select(
        'id',
        "CONCAT(first_name, ' ', last_name) as full_name",
        'username',
        'email',
    )
    ->get();

// The SQL Laravel actually sends
select `id`, `CONCAT(first_name, ' ', last_name) as full_name`, `username`, `email`
from `users` where `id` = ?;

MySQL parses those backticks, looks for a column literally named CONCAT(first_name, ' ', last_name) as full_name, doesn’t find one, and raises:

SQLSTATE[42S22]: Column not found: 1054 Unknown column 'CONCAT(first_name, ...) as full_name' in 'field list'

Fix 1 — Wrap in DB::raw()

The minimal change: import the DB facade and wrap the raw expression. Everything else in the select() list stays normal.

use Illuminate\Support\Facades\DB;

User::where('id', '=', 10)
    ->select(
        'id',
        DB::raw("CONCAT(first_name, ' ', last_name) as full_name"),
        'username',
        'email',
    )
    ->get();

Laravel now sees the DB::raw expression instance, knows not to escape it, and interpolates the SQL verbatim. MySQL runs CONCAT() like you’d expect, and full_name comes back as a real attribute on each returned model.

Fix 2 — selectRaw()

If every column in your select list is a raw expression, selectRaw() is less noisy — one call, one string, optional bindings:

User::where('id', '=', 10)
    ->selectRaw(
        "id, CONCAT(first_name, ' ', last_name) as full_name, username, email"
    )
    ->get();

The whole string is treated as raw SQL, so the non-expression columns (id, username, email) are also emitted unescaped. That’s fine for columns you control — risky for anything user-supplied. The rule below applies to both forms.

Safety — never interpolate user input into a raw expression

Anything inside DB::raw() or selectRaw() bypasses Laravel’s parameter binding, which means it bypasses SQL-injection protection too. Never concatenate request input into the raw string:

// NEVER do this — $request->separator is attacker-controlled
DB::raw("CONCAT(first_name, '{$request->separator}', last_name)")

// Safe — pass dynamic values via bindings
User::selectRaw(
    "CONCAT(first_name, ?, last_name) as full_name",
    [$request->separator]
)->get();

Both selectRaw() and the ->where('...', [bindings]) variants accept an array of bindings as the second argument. Use those for anything dynamic; keep literal SQL reserved for column names and function calls you fully control.

Alternative — compute in PHP with an accessor

If you only need full_name for display and not for filtering or ordering, skip the SQL concatenation entirely and define an Eloquent accessor:

// app/Models/User.php
use Illuminate\Database\Eloquent\Casts\Attribute;

protected function fullName(): Attribute
{
    return Attribute::get(fn () => trim("{$this->first_name} {$this->last_name}"));
}

Now $user->full_name works on every model instance without changing any query. Reach for the SQL CONCAT approach when you need to ORDER BY full_name, WHERE full_name LIKE ?, or GROUP BY a concatenated value — cases the accessor can’t handle because the value doesn’t exist in the database.

Frequently asked questions

Related guides

• How to Use Multiple where and orWhere in Laravel Eloquent — combining raw expressions with bound conditions.
• How to Use Order By in Eloquent Laravel — ordering by a computed column like the one CONCAT produces.
• How to Do a Left Outer Join with Laravel — another case where raw SELECT lists come up.
• How to Install Laravel on Ubuntu — Laravel 11 setup before you touch Eloquent.

References

Official Laravel query-builder docs (DB::raw, selectRaw, raw expressions): laravel.com/docs/queries. MySQL CONCAT reference: dev.mysql.com/doc/refman/8.0.