# Procedures

## What is a Stored Procedure?

A stored procedure is SQL code that can be accessed using SQL `CALL` syntax. Much like a function in other programming languages, you can pass values into a stored procedures. Results are returned as a table.

Database users create procedures. Procedures are schema and are stored along with other schema elements in the database.

## How to use Stored Procedures

Stored Procedures are used to store code you want the database to execute when a user asks. In Dolt, we use built in stored procedures to allow users to do version control write operations, like create a commit.

## Difference between MySQL Stored Procedures and Dolt Stored Procedures

Dolt stored procedures match MySQL stored procedures exactly.

Dolt exposes custom [stored procedures for version control operations](https://docs.dolthub.com/sql-reference/version-control/dolt-sql-procedures). These are named after the corresponding Dolt commands.

## Interaction with Dolt Version Control

Procedures are versioned in the `dolt_procedures` table. You add and commit that table just like any other changed table after you create or modify a trigger.

## Example

```
mysql> CREATE PROCEDURE example(x INT) SELECT x + 1;
mysql> call example(1);
+---------+
| (x + 1) |
+---------+
| 2       |
+---------+
```

### `dolt_procedures` table

```
mysql> select * from dolt_status;
+-----------------+--------+----------+
| table_name      | staged | status   |
+-----------------+--------+----------+
| dolt_procedures | 0      | modified |
+-----------------+--------+----------+
mysql> select * from dolt_procedures;
+---------+----------------------------------------------+----------------------------+----------------------------+
| name    | create_stmt                                  | created_at                 | modified_at                |
+---------+----------------------------------------------+----------------------------+----------------------------+
| example | CREATE PROCEDURE example(x INT) SELECT x + 1 | 2022-06-24 18:21:44.125045 | 2022-06-24 18:21:44.125045 |
+---------+----------------------------------------------+----------------------------+----------------------------+
```