Accessing relational databases
Using Go, you can incorporate a wide variety of databases and data access
approaches into your applications. Topics in this section describe how to use
the standard library's
package to access relational databases.
For an introductory tutorial to data access with Go, please see Tutorial: Accessing a relational database.
Go supports other data access technologies as well, including ORM libraries for higher-level access to relational databases, and also non-relational NoSQL data stores.
- Object-relational mapping (ORM) libraries. While the
database/sqlpackage includes functions for lower-level data access logic, you can also use Go to access data stores at a higher abstraction level. For more about two popular object-relational mapping (ORM) libraries for Go, see GORM (package reference) and ent (package reference).
- NoSQL data stores. The Go community has developed drivers for the majority of NoSQL data stores, including MongoDB and Couchbase. You can search pkg.go.dev for more.
Supported database management systems
Go supports all of the most common relational database management systems, including MySQL, Oracle, Postgres, SQL Server, SQLite, and more.
You'll find a complete list of drivers at the SQLDrivers page.
Functions to execute queries or make database changes
database/sql package includes functions specifically designed for the
kind of database operation you're executing. For example, while you can use
QueryRow to execute queries,
QueryRow is designed for the case
when you're expecting only a single row, omitting the overhead of returning
sql.Rows that includes only one row. You can use the
to make database changes with SQL statements such as
For more, see the following:
sql.Tx, you can write code to execute database operations in a
transaction. In a transaction, multiple operations can be performed together
and conclude with a final commit, to apply all the changes in one atomic
step, or a rollback, to discard them.
For more about transactions, see Executing transactions.
You can use
context.Context when you want the ability to cancel a database
operation, such as when the client's connection closes or the operation runs
longer than you want it to.
For any database operation, you can use a
database/sql package function
Context as an argument. Using the
Context, you can specify a
timeout or deadline for the operation. You can also use the
propagate a cancellation request through your application to the function
executing an SQL statement, ensuring that resources are freed up if they're
no longer needed.
For more, see Cancelling in-progress operations.
Managed connection pool
When you use the
sql.DB database handle, you're connecting with a built-in
connection pool that creates and disposes of connections according to your
code's needs. A handle through
sql.DB is the most common way to do
database access with Go. For more, see
Opening a database handle.
database/sql package manages the connection pool for you. However, for
more advanced needs, you can set connection pool properties as described in
Setting connection pool properties.
For those operations in which you need a single reserved connection, the
database/sql package provides
Conn is especially useful when a transaction with
sql.Tx would be a
For example, your code might need to:
- Make schema changes through a DDL, including logic that contains its
own transaction semantics. Mixing
sqlpackage transaction functions with SQL transaction statements is a poor practice, as described in Executing transactions.
- Perform query locking operations that create temporary tables.
For more, see Using dedicated connections.