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.

Dolt is MySQL-compatible. I use Postgres?

We released a Postgres version of Dolt called DoltgreSQL.

However, Dolt is a production-grade version controlled database today. Dolt is 1.0. If you are ok with using a MySQL-client, we recommend using Dolt for all use cases. Doltgres is experimental.

What does @@autocommit do?

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

SET @@autocommit = 1

It's on by default in the MySQL shell, as well as in most clients. But some clients (notably the Python MySQL connector) turn it off by default.

You must commit your changes for them to persist after your session ends, either by setting @@autocommit to on, or by issuing COMMIT statements manually.

What's the difference between 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.

DOLT_COMMIT() commits the current SQL transaction, then creates a new dolt commit on the current branch. It's the same as if you run dolt commit from the command line.

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

We are glad you asked! This is a common use case, and giving each user their own branch is something we've spent a lot of time getting right. For more details on how to use this pattern effectively, see using branches.

Does Dolt support transactions?

Yes, it should exactly work the same as MySQL, but with fewer locks for competing writes.

It's also possible for different sessions to connect to different branches on the same server. See using branches for details.

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? We have blogs and sample code for many popular ORMs and tools.

If you try it and it doesn't work, let us know with an issue or in our Discord and we'll fix it in 24 hours. Our goal is to be a 100% drop-in replacement for MySQL.

Why does Dolt use so much disk space?

Dolt generates a lot of garbage during some writes, especially during initial import. As of Dolt 1.75, Dolt collects disk garbage non-intrusively by default, a feature called automatic garbage collection. So, users of the newest Dolt versions should not notice high disk usage. If you do see unusually high disk usage, you can manually initiate garbage collection by calling dolt_gc().

How do I squash the history of a Dolt database? I only want the latest.

You can perform a shallow clone of a database by using the --depth flag. If you only want the latest change, specify a depth of 1. The CLI also supports this:

dolt clone --depth 1 <database>

Does Dolt collect client metrics? How can I disable it?

Dolt collects anonymous usage metrics and sends them over the network to DoltHub metrics servers. No personally identifiable information is collected. You can disable this behavior by setting the metrics.disabled config key:

dolt config --global --add metrics.disabled true

How to silence stats failure logs?

Statistic warnings appear infrequently between dolt version upgrades and do not impact the correctness of database operations. If the error is reproducible please report the issue.

Statistics caches can be removed from the filesystem to silence warnings with dolt_stats_purge():

call dolt_stats_purge();

Version incompatibilities should not hinder the purge command, but if manual intervention is desirable a specific database's stats cache can be removed from the filesystem:

rm -rf .dolt/stats

Statistics can be recollected at any time to improve join and indexing execution performance. See the stats docs for more details.