Adapters

Four engines, and exactly what each one can and cannot do.

DataGripe supports PostgreSQL, MySQL, SQLite and Redis. They are not equally capable, and the interface says so rather than offering you an action that fails at runtime.

Every adapter declares a set of capability flags. The UI and the request dispatcher gate on those flags and never on the adapter's name, which is the mechanism that makes the honesty structural rather than a matter of remembering.

What each one can do

The table below is generated from ADAPTER_CAPABILITIES in the repository — the same constant the application itself gates on, so this page cannot describe an engine the app does not.

— means the adapter does not have the capability at all, and the corresponding control is absent rather than disabled with a tooltip.

Reading the flags

Explorer. sql gives the schema → table → column tree. keyspace gives Redis's database → prefix → key browser, split on the : delimiter, with a truncation marker where a level exceeded its scan bound.

Execution. cursor is a server-side cursor with batched fetches, so a large result streams and the first rows arrive immediately. buffered fetches the whole result and truncates it to QUERY_MAX_ROWS and QUERY_MAX_BYTES. Where execution is absent, execution.start is rejected server-side and the run buttons are disabled client-side — both, because a client-side check is a convenience and a server-side one is the rule.

Cancellation. True means cancelling interrupts the running statement on the server, down an administrative control path that is not the one being blocked. That is the only reason cancel works on a query that is stuck, which is the only time it matters. SQLite has no driver-level interrupt; local files make a runaway query cheap to bound by caps instead.

Table view. readwrite browses rows and writes single-row edits back in one transaction. Where it is absent, double-clicking an object opens a tab that says so rather than rendering an empty grid.

Column changes. A list rather than a boolean, and SQLite is the reason. Its ALTER TABLE does add, rename and drop and nothing else, so the columns tab enables per operation and says why the rest are off. A type, nullability or default change needs the twelve-step table rebuild, which is on the roadmap.

Access report. PostgreSQL only. MySQL's grant model is different enough — host-qualified grantees, no roles before 8.0 — to be a separate design rather than a port, and SQLite has no grants at all.

Per-engine notes

PostgreSQL

The reference implementation, and the only one with everything. Cursor streaming, KILL-equivalent cancellation from a second connection, reconstructed DDL, routines and sequences in the object view, the access report, and the grant.* and routine.* rules.

It is also the only engine where CREATE INDEX CONCURRENTLY exists, which is why index.not-concurrent is gated on the dialect: on MySQL and SQLite that advice is not merely unhelpful, it is a syntax error.

MySQL

Introspection through information_schema, system schemas excluded. Timeouts are enforced primarily by SET SESSION max_execution_time, with a client-side watchdog as the deterministic backstop; cancellation is KILL QUERY from a second connection.

One driver quirk is worth knowing because it shaped the design: Bun's MySQL driver resolves an interrupted statement cleanly — SLEEP returns 1, no error, empty SHOW WARNINGS. Outcomes are therefore tracked out of band rather than inferred from the driver's response, or a cancelled query would report success.

allowPublicKeyRetrieval is set only when TLS is disabled, which is the caching_sha2_password-over-plain-TCP case on a trusted local link. TLS modes never set it.

SQLite

The database field is a server-side file path, not a database name, and host, port, username and TLS are all absent from its dialog. That means the file has to be reachable from wherever the server runs — which is your own machine in the personal and desktop shapes, and probably not what you want in a hosted deployment.

Schemas come from PRAGMA database_list (main plus attached), objects from sqlite_master, columns from PRAGMA table_info. readOnly opens the file read-only at the driver level rather than filtering statements.

Redis

A distinct capability rather than a limited SQL engine. The browser is read-only: PING to test, a SCAN-bounded keyspace tree at 10,000 keys per level with a truncation marker, and value fetches for strings, hashes, lists, sets and sorted sets with a TTL and a 100-entry cap.

There is no query execution, so the run controls are absent. Whether Redis earns command execution later is an open question, and it would be a new capability flag rather than pretending it speaks SQL.

Adding one

An adapter is an implementation and one entry in ADAPTER_CAPABILITIES. There is no third place to update, and nothing in the UI branches on the adapter's name — which is what lets a new engine appear with its own honest set of limits instead of a set of runtime surprises.

SQL Server is the one most often asked for. It is on the roadmap as unscheduled, which means nobody is working on it.

Related

• What it can do — the surface all four share.
• The rules — which rules are dialect-gated.
• The adapters spec — the capability model, the driver quirks, and the open questions.

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