Skip to content

Document unstable_sqlite_expression_engine #485

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
simolus3 wants to merge 3 commits into
base: main
Choose a base branch
from
Open

Document unstable_sqlite_expression_engine #485

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
eeb435b
Document `unstable_sqlite_expression_engine`
simolus3 Jun 1, 2026
b4606a6
Review feedback
simolus3 Jun 4, 2026
6a50afe
Apply suggestion from @benitav
benitav Jun 4, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
16 changes: 16 additions & 0 deletions sync/advanced/compatibility.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -99,6 +99,7 @@ This table lists all fixes currently supported:
| `versioned_bucket_ids` | [Link](#versioned-bucket-ids) | 1.15.0 | 2 |
| `fixed_json_extract` | [Link](#fixed-json-extract) | 1.15.0 | 2 |
| `custom_postgres_types` | [Link](#custom-postgres-types). | 1.15.3 | 2 |
| `unstable_sqlite_expression_engine` | [Link](#unstable_sqlite_expression_engine). | 1.22.0 | None (unstable) |

### `timestamps_iso8601`

Expand Down Expand Up @@ -190,3 +191,18 @@ With this fix applied:
| 'empty';
```
- Multi-ranges sync as an array of ranges.

### `unstable_sqlite_expression_engine`

<Danger>
This option is experimental: When enabled, updates to the PowerSync Service might change how rows are processed
and this option may be removed in a future version of the Service.
</Danger>

Sync Streams support scalar SQL operators (like `+`, `-` and `||`) and [functions](/sync/supported-sql#functions).
SQL in Sync Streams should behave exactly as it would in SQLite, but the Service uses a custom implementation which differs
from SQLite for some edge cases.

To perfectly align the behavior of the Service and SQLite, enabling this option makes the Service use an actual
Copy link
Copy Markdown
Collaborator

@benitav benitav Jun 4, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It's not clear what this means practically? can we mention an example?

Copy link
Copy Markdown
Contributor Author

@simolus3 simolus3 Jun 4, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

We've fixed most of the issues that are unlikely to break users. I've added a remaining example.

Copy link
Copy Markdown
Collaborator

@benitav benitav Jun 4, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Is this still true? Enabling unstable_sqlite_expression_engine requires fixed_json_extract (fro mthe original PR). If so would be good to add here too.

SQLite database to evaluate Sync Streams.
For example, the expression `NOT NULL` evaluates to `TRUE` without this option, enabling it yields `NULL`.