usqlgen

usqlgen creates custom distributions of github.com/xo/usql - a universal single-binary SQL CLI, built by the github.com/xo team, and inspired by psql.

usql is great because it is a multi-platform, multi-database SQL client in a single binary. Learn more about it from its README.

usqlgen builds on usql's extensibility to allow including arbitrary drivers and other customizations, without needing to fork.

When to use

In most cases, using usql directly is best. usqlgen helps when you want to avoid editing usql code and:

• you want to use a database driver which is not publicly available or is under active development
• you want to use alternative driver for a database supported by usql.
• you want to use a different version or a fork of a bundled driver
• you are working with a niche database which is not supported by usql yet
  • consider contributing the support to usql at some point

The Examples section details those usecases.

usqlgen is itself inspired by the OpenTelemetry Collector builder.

Important

usql authors are aware of this project but support only their regular releases. Issues that appear on builds produced by usqlgen should be reported on this repository. Report issues on https://github.com/xo/usql/issues only if you can reproduce them on a regular release.

Installing

Install usqlgen with Go 1.21+:

go install github.com/sclgo/usqlgen@latest

You can also run usqlgen without installing:

go run github.com/sclgo/usqlgen@latest

If you don't have Go 1.21+, you can run usqlgen with Docker:

docker run --rm golang:1.23 \
  go run github.com/sclgo/usqlgen@latest build ...add parameters here... -o - > ./usql

chmod +x ./usql

Ensure that the Docker image matches the OS you are using - Windows container for Windows, Alpine for Alpine Linux, etc. The default golang image works for Debian-based Linux distributions like Ubuntu.

Quickstart

To install usql with support for an additional driver, first review your driver documentation to find the Go driver name, DSN (Data Source Name) format and package that needs to be imported to install the driver. Let's take for example, MonetDB, which is not in usql yet. The docs state that the package that needs to be imported is github.com/MonetDB/MonetDB-Go/v2. We use this command to build usql:

usqlgen build --import "github.com/MonetDB/MonetDB-Go/v2"

This creates usql executable in the current directory with its default built-in drivers together with the driver for MonetDB. The additional driver is registered using a side-effect import (aka blank import) of the package in the --import parameter. The respective module is automatically determined but can also be specified explicitly with --get.

Unlike built-in databases, the usql DB URL (connection string) for the new database is in the form driverName:dsn. For example, MonetDB docs state that the driver name is monetdb and the DSN format is username:password@hostname:50000/database. So to connect to MonetDB with the binary we just built, run:

# The command below is configured to connect to a local MonetDB started like this:
# docker run -p 50000:50000 -e MDB_DB_ADMIN_PASS=password monetdb/monetdb:latest

./usql monetdb:monetdb:password@localhost:50000/monetdb -c "select 'Hello World'"

Above monetdb is repeated in the beginning of the DB URL because it is both the Go driver name, and the admin username in the beginning of the DSN.

You can try the same with databases or data engines like rqlite, Dremio or Apache Drill, etc.

usqlgen also allows you to use alternative drivers of supported databases. Examples include:

• github.com/microsoft/gocosmos - an official mirror of the unofficial driver included in usql
• github.com/yugabyte/pgx - Postgres pgx variant by Yugabyte with cluster-aware load balancing
• github.com/mailru/go-clickhouse/v2 - HTTP-only alternative of the built-in Clickhouse driver
• github.com/sclgo/adbcduck-go - alternative driver for DuckDB that uses its ADBC C API

For more options, see usqlgen --help or review the examples below.

Limitations

Most usql backslash (meta) commands work with new drivers added with --import, including cross-database \copy. Informational commands and autocomplete won't work though - for now.

usql requires that connection strings are valid URIs or URLs, at least according to the Go net/url parsing algorithm. If you get an error that parameter in the form driverName:dsn can't be parsed as a URL, start usql without a connection string - in interactive mode or with the -f parameter. usql will start not connected to a DB. Then use the \connect command with two arguments driverName and dsn. In the monetdb example above, that would be: \connect monetdb monetdb:password@localhost:50000/monetdb.

CGO usage

usqlgen build and usqlgen install usually require support for CGO to compile the generated usql codebase. If you need to avoid depending on CGO:

• don't import drivers that use CGO. The driver documentation should mention such usage.
• exclude usql base drivers that depend on CGO by adding -- -tags no_sqlite3 to the usqlgen command-line

If the system doesn't support CGO you may see errors like this when running usqlgen build or install:

# github.com/xo/usql/drivers/sqlite3
drivers/sqlite3/sqlite3.go:31:29: undefined: sqlite3.Error
drivers/sqlite3/sqlite3.go:35:29: undefined: sqlite3.ErrNo

In the future, usqlgen will detect if CGO is not available and automatically exclude default drivers that need it and weren't explicitly requested. usqlgen itself does not require CGO to compile or install.

Examples

Installing the customized usql

Use usqlgen install ... to install the customized usql to GOPATH/bin which is typically on the search path. This runs go install internally.

usqlgen install --import "github.com/MonetDB/MonetDB-Go/v2"
usql -c '\drivers' | grep monetdb
# prints
#   monetdb [mo]

Adding compilation options

usqlgen build and usqlgen install call go build and go install respectively. You can pass options directly to the go commands after the -- parameter. For example, the following command supplies go build tag no_base which removes all built-in usql drivers so only the custom one we add remains:

usqlgen build --import "github.com/MonetDB/MonetDB-Go/v2" -- -tags no_base
./usql -c '\drivers'
# prints only a single driver

In this case, the binary will be smaller and faster to build.

Review https://github.com/xo/usql?tab=readme-ov-file#building for build tags, supported by usql and the documentation of go build and go install for other options.

Go environment variables like GOPRIVATE or CGO_ENABLED affect the compilation as usual. For example, GOPRIVATE allows you to compile usql with drivers which are not publicly available.

Using a driver fork

usqlgen can build usql with a replace directive so that you can use a SQL driver fork while keeping the usql configuration for the target database. Information commands, schema exploration, and autocomplete will continue to work if the fork remains compatible enough with the original.

For example, github.com/dlapko/go-mssqldb is a fork of github.com/microsoft/go-mssqldb with several fixes at the time of writing.

To build usql with the fork, run:

usqlgen build --replace "github.com/microsoft/go-mssqldb=github.com/dlapko/go-mssqldb@main"

Note that this works only with forks that keep the original module name - in this case github.com/microsoft/go-mssqldb - in their go.mod. Such forks can only be used as replacements and can't be imported directly. For example, this command doesn't work:

usqlgen build --import "github.com/dlapko/go-mssqldb"
# the error output includes:
module declares its path as: github.com/microsoft/go-mssqldb
        but was required as: github.com/dlapko/go-mssqldb      

Forks that changed the module name to match their repository location can be imported with --import, e.g. github.com/yugabyte/pgx .

Using a specific version of a driver

If you are not happy with some driver or library version bundled with usql, you can change it in two ways.

The preferred approach is adding --get parameter to execute go get while building. go get may adjust other dependencies to ensure compatibility with the updated version.

usqlgen build --get "github.com/go-sql-driver/[email protected]"

If the adjustments made by go get are not wanted, you may add a replace directive instead:

usqlgen build --replace "github.com/go-sql-driver/mysql=github.com/go-sql-driver/[email protected]"

Support

If you encounter problems, please review open issues and create one if nessesary. Note that usql authors are aware of this project but support only their regular releases.