FAQ

Why is it called Dolt? Are you calling me dumb?

It's named dolt to pay homage to how Linus Torvalds named git:

Torvalds sarcastically quipped about the name git (which means "unpleasant person" in British English slang): "I'm an egotistical bastard, and I name all my projects after myself. First 'Linux', now 'git'."

We wanted a word meaning "idiot", starting with D for Data, short enough to type on the command line, and not taken in the standard command line lexicon. So, dolt.

Why does my connection to the server hang / time out?

With no config file, the server starts up in single user mode. It won't allow a second connection until the first hangs up. This is to prevent any unpleasant surprises with multiple writers, since Dolt's transaction / concurrency model is a work in progress.

To allow multiple simultaneous connections, set the max_connections field in the config.yaml file you pass to the dolt sql-server command, as described in the docs.

The MySQL shell gives me an error: Can't connect to local MySQL server through socket '/tmp/mysql.sock'

The MySQL shell will try to connect through a socket file on many OSes. To force it to use TCP instead, give it the loopback address like this:

% mysql --host 127.0.0.1 ...

What does @@autocommit do?

This is a SQL variable that you can turn on for your SQL session like so:

SET @@autocommit = 1

If it's set to a true value, then Dolt will flush your changes to disk after every SQL statement, so that you can see your changes when you run other commands (like dolt diff) from the command line. Specifically, it updates the working set in your database state, the same way that running dolt sql -q ... on the command line does.

Otherwise, you won't see changes outside your session until you issue a COMMIT statement. See the next question.

What's the difference between COMMIT, COMMIT(), and DOLT_COMMIT()?

COMMIT is a standard SQL statement that commits a transaction. In dolt, it just flushes any pending changes in the current SQL session to disk, updating the working set. HEAD stays the same, but your working set changes. This means your edits will persist after this session ends.

COMMIT() creates a new dolt commit, but doesn't reference it anywhere. If you want to reference it, you have to take the value returned by the function and create a branch with it (by inserting into dolt_branches)

DOLT_COMMIT() is the same as if you run dolt commit from the command line. It updates HEAD.

See the docs on concurrency.

I want each of my connected SQL users to get their own branch to make changes on, then merge them back into master when they're done making edits. How do I do that?

We are glad you asked! This is a common use case, and we wrote a couple blog articles about how to do this effectively.

dolt sql-server concurrency

Merging and resolving conflicts programmatically with SQL

Does Dolt support transactions?

Yes, but it's an alpha release that may have some rough edges, so it's not enabled by default. To turn it on, set an environment variable:

export DOLT_ENABLE_TRANSACTIONS=true

See this blog post for more details.

Named locks work, via GET_LOCK() and RELEASE_LOCK() functions.

Better support for transactions, concurrency, and row-level locking is on our roadmap.

What SQL features / syntax are supported?

Most of them! Check out the docs for the full list of supported features.

You can check out what we're working on next on our roadmap. Paying customers get their feature requests bumped to the front of the line.

Does Dolt support my favorite SQL workbench / tool?

Probably! Have you tried it? If you try it and it doesn't work, let us know with an issue or in our Discord and we'll see what we can do. A lot of times we can fix small compatibility issues really quick, like the same week. And even if we can't, we want to know about it! Our goal is to be a 100% drop-in replacement for MySQL.