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Database Beginner 175 views

Unknown Column

The SQL query references a column that doesn't exist in the specified table.

Explanation

Unknown column is a database error indicating that a SQL query references a column that doesn't exist in the table. This commonly happens when a migration adding a new column hasn't been run, when column names are misspelled, when querying a view that doesn't include the column, or when the database schema has changed but the application code hasn't been updated. In Laravel, this can also happen when Eloquent model attributes don't match the actual database columns.

Common Causes

  • Migration not run for new column
  • Column name misspelled
  • Database schema changed
  • Model attributes don't match columns
  • Querying wrong table

Solution

Run pending database migrations: php artisan migrate. Check column name spelling in your queries. Verify the table structure: DESC table_name in MySQL or \d table_name in PostgreSQL. Review recent migrations to ensure they created the expected columns. For Eloquent, verify that \$fillable and \$guarded arrays match actual columns. Clear any cached schema information. Check that the model's table property points to the correct table.

Code Example 

// Eloquent query referencing non-existent column
$users = User::where('phone_number', '123')->get();
// Error if 'phone_number' column doesn't exist

// Fix: check table structure first
// MySQL: DESCRIBE users;
// PostgreSQL: \d users

// Run missing migrations
php artisan migrate

// Check if column exists before querying
if (Schema::hasColumn('users', 'phone_number')) {
    $users = User::where('phone_number', '123')->get();
}

// Add missing column via migration
Schema::table('users', function (Blueprint $table) {
    $table->string('phone_number')->nullable();
});

// Verify model attributes
class User extends Model
{
    protected $fillable = ['name', 'email', 'phone_number'];
}

Error Information

Language

php

Framework

laravel

Difficulty

Beginner

Views

175

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