Ever used SQL clients or database management software? You know, DbVisualizer, Percona Monitoring and Management, or others? If you did, you probably remember the times when you had to specify the database you’re working with for the tool to assist you. And you surely remember the necessity to specify a DSN format in the process, right? You do — specifying a connection string — or a DSN — is a necessity to connect to any database. In this blog, we explore the Golang MySQL DSN format too.
What Is a Database Connection String?
Before we begin, we have to step back a little and understand what DSN or a connection string actually is in the first place. DSN—which stands for a Data Source Name—and a connection string is the same thing, just with a different name.
In other words, a connection string is the data source name and it may take different forms since there is no exact specification on what it looks like. For example, it may look like so:
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scheme://username:password@host:port/database_name?parameter=value&anotherparameter=another_value¶m3=value3...
When connecting to MySQL, this is what it usually looks like:
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mysql://user:password@host/databasename
And, when using SSL:
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mysql://user:password@host/pear?key=client-key.pem&cert=client-cert.pem
Or it can also take other forms.
Many users notice that the MySQL DSN differs from the one used for PostgreSQL. This may be because the PDO driver for PostgreSQL does not require updates when the underlying library introduces new features, among other possible reasons.
What Is the MySQL DSN Format for Golang?
Given that, many users find themselves asking the question, What’s the Golang MySQL DSN format? There are websites specifically designed to help users understand SQL in Golang, but they don’t seem to define these things. So, back to the question — what about the Golang MySQL DSN format?
In the github.com/go-sql-driver/mysql library, the DSN format is:
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[username[:password]@][protocol[(address)]]/dbname[?param1=value1&...¶mN=valueN]
So, a DSN in its fullest form will follow this format:
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username:password@protocol(address)/dbname?param=value
Where address typically have this format:
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host:port
Where port is generally 3306, the default MySQL port.
To test that, add github.com/go-sql-driver/mysql to your Go’s projects dependencies with:
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go get github.com/go-sql-driver/mysql
Then, use it to connect to your db with this logic:
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package main
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import (
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"database/sql"
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_ "github.com/go-sql-driver/mysql"
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)
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func main() {
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db, err := sql.Open("mysql", "your_username:your_password@tcp(hostname:3306)/db_name")
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}
In short, the following Golang MySQL DSN format should be good to go in most cases:
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your_username:your_password@tcp(hostname:3306)/db_name
Other Things to Care About
Let’s face it — knowing how to specify the Golang MySQL DSN format is basic knowledge. If you’re a DBA, you have more things to care about: and the performance of your databases is one of them.
Thankfully for you, you’re not alone in this realm — with tools like DbVisualizer at the helm, riding the database performance highway is easier than ever before. All you have to do is import the database in question into the tool (DbVisualizer supports more than 50 data sources, too — did you know it?) and then start squashing the bugs. Exploring the databases and the table structure underneath in your database management system of choice is a good starting point. Click around and you will quickly notice that DbVisualizer provides all of the necessary information for you to start optimizing your queries (once you optimize them, you can easily maintain partitions/indexes using the tool too):
If you want to, you can easily explore the structure of your tables and their relation to other tables by exploring the References tab too:
These kinds of small things have a big impact on your application and your database — thus, you cannot afford to neglect them. DbVisualizer won’t let you do that — grab a free 21-day trial and try DbVisualizer free of charge today, then tell us what you think!
Summary
The Golang MySQL DSN format is of interest to many developers and this blog has shown you a way to use it in a real-world example. We hope that you’ve found this blog to be educational and useful and that you will come back to TheTable to read some more of our content.
In the meanwhile, grab a free 21-day trial of DbVisualizer to help your databases succeed, and until next time!
FAQ
What is the Golang MySQL DSN Format?
There is no “standard” for the Golang MySQL DSN format, however, the one below should work just fine with the Go-MySQL-Driver library:
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your_username:your_password@tcp(hostname:3306)/db_name
Why should I use DbVisualizer?
Consider using SQL clients like the one provided by DbVisualizer because features within tools like DbVisualizer can help any kind of database understand why the queries within itself are underperforming, help you rebuild your database schema, normalize your databases, run your queries in a visual fashion, and accomplish a bunch of other things you didn’t even think about!
How do I further optimize MySQL instances for performance?
Consider following TheTable on DbVisualizer or read books — Hacking MySQL: Breaking, Optimizing, and Securing MySQL for Your Use Case is a good place to start.
