SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes

 Error:

SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes (Connection: mysql, SQL: alter table `permissions` add unique `permissions_name_guard_name_unique`(`name`, `guard_name`))

When working with databases, encountering SQL errors is a common part of the development process. One such error that can perplex developers is the SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes. This error occurs when trying to create or alter a table with an index that exceeds the maximum allowed size. Understanding and fixing this error is crucial for maintaining the integrity and performance of your database. Here's a brief guide on what causes this error and how to resolve it.

Understanding the Error

The Specified key was too long; max key length is 1000 bytes error usually occurs in MySQL or MariaDB databases when an index creation attempts exceed the maximum length allowed by the storage engine. Most commonly, this happens with string columns (VARCHAR, CHAR, TEXT) that are set to a length which, when combined with the character set's maximum byte length, exceeds the limit. For instance, using UTF-8 characters can require up to 3 bytes per character, and UTF-8mb4 can require up to 4 bytes per character.

Causes of the Error

Character Set and Collation: The choice of character set (like utf8mb4) with a higher byte-per-character ratio can quickly consume the byte limit for indexes.
Column Size: Large column sizes, especially for VARCHAR or TEXT types, when indexed.
Composite Indexes: Creating a composite index that includes several string columns can also lead to exceeding the maximum key length.

How to Resolve

Upgrade Your Database Engine:

In laravel 10 go to the location config/database.php

update engine to innodb

Adjust Column Sizes: Review and reduce the size of the columns being indexed. If a column is declared as VARCHAR(255) but typically contains much shorter strings, consider decreasing its size.

Change Character Set: For columns that don't require the storage of 4-byte characters, switching from utf8mb4 to utf8 can reduce the size of the index.