v0.2.0-alpha.4

Contributed in part by Jose Davila-Ciullo (@jdctinuiti) — thanks!

Added

• Token provider properties for safer shared JDBC configurations:
  tokenEnv and tokenFile. Both are accepted via connection
  Properties only — they are rejected on the JDBC URL so that a pasted
  or shared URL cannot read a local secret and send it to an
  attacker-chosen host.

Fixed

• Manual-commit transactions now work with DataGrip, DBeaver, and other
  tools (#4). With autoCommit off, the driver lazily issues
  BEGIN TRANSACTION before the first statement, so a later
  Connection.commit() no longer fails with
  "cannot commit - no transaction is active". commit()/rollback()
  with no pending transaction are harmless no-ops, and re-enabling
  auto-commit mid-transaction commits it per the JDBC spec.
• HTTPS transport now keeps the original hostname in request URIs instead
  of replacing it with a resolved IP address. This preserves TLS SNI and
  certificate hostname verification for gateways and load balancers that
  route by hostname. Plain HTTP endpoints still expand to resolved address
  candidates for the existing localhost IPv4/IPv6 fallback behavior.

v0.2.0-alpha.3

Supersedes the never-published v0.2.0-alpha.2 tag (Maven Central
rejected the re-publish after the original tag's deploy was cancelled
mid-flight). Content is identical to what alpha.2 would have shipped,
plus contributor credit in the [0.2.0-alpha.1] notes below.

Changed

• Integration tests now INSTALL quack; from the core repository,
  matching DuckDB v1.5.3 ("Variegata") where Quack ships as a signed
  core extension. The -unsigned flag and core_nightly repository are
  no longer required. The full 83-test suite passes against the
  quack extension bundled with DuckDB CLI v1.5.3 — no driver code
  changes needed, the wire format is unchanged.
• README and CLAUDE.md updated to reflect the v1.5.3 install path; the
  pre-1.5.3 INSTALL quack FROM core_nightly recipe is kept as a note
  for users on older builds.

v0.2.0-alpha.1

Thanks to @mwieczorkiewicz
(Mikołaj Wieczorkiewicz) for contributing the pluggable transport SPI
and configurable HTTP timeouts in #1
— their first contribution to the project.

Added — Pluggable transport SPI (#1)

• QuackTransport interface and QuackTransportFactory
  (functional, takes a parsed QuackUri) let applications supply their
  own transport implementation — a custom HttpClient with proxies /
  mTLS / interceptors, or an in-process fake for testing.
• QuackDriver.connect(url, properties, transportFactory) overload
  threads the factory through QuackConnection and QuackSession. The
  no-factory connect(url, properties) path is unchanged and still uses
  the built-in HTTP transport.
• QuackHttpTransport now implements QuackTransport; the existing
  QuackSession(QuackUri, QuackHttpTransport) constructor is retained
  for binary compatibility.

Added — Configurable HTTP timeouts

• connectTimeout and requestTimeout JDBC URL / Properties
  options, accepted as either a plain integer (seconds) or an ISO-8601
  duration like PT30S. Defaults remain 10s connect / 60s request.
  Surfaced via Driver.getPropertyInfo so DBeaver / DataGrip show them
  in their connection dialogs.
• Invalid / non-positive values raise a QuackException at parse time.

Tests

• New QuackDriverCustomTransportTest exercising factory injection,
  null-factory error handling, getPropertyInfo shape, and binary
  compatibility of the legacy QuackSession constructor.
• New QuackUriTest cases for timeout parsing (URL, properties, invalid
  values) and a QuackHttpTransportTest case for from(QuackUri).

Total suite: 83 tests, all green.

v0.1.0-alpha.1

Published to Maven Central as
com.gizmodata:quack-jdbc:0.1.0-alpha.1 and as a GitHub Release with
both versioned and un-versioned jars at
https://github.com/gizmodata/quack-jdbc/releases/tag/v0.1.0-alpha.1.

First public alpha release. The Quack protocol itself is in beta until
DuckDB v2.0 ships in September 2026 — this driver is pinned to
duckdb/duckdb-quack@daae4826
(2026-05-10). Don't use this in production; do use it to evaluate
DBeaver / DataGrip / Spark / direct JDBC against a remote DuckDB.

All [Unreleased] entries below shipped in this release.

Added — Release distribution

• GitHub Release jars are now attached to every tagged release by
  CI, in addition to the versioned artifact going to Maven Central.
  Each release gets:
  • quack-jdbc-<version>.jar — versioned filename
  • quack-jdbc.jar — un-versioned filename (always the latest), so
    DBeaver / DataGrip / curl users can fetch a stable URL:
    https://github.com/gizmodata/quack-jdbc/releases/latest/download/quack-jdbc.jar
  • Matching *-sources.jar and *-javadoc.jar in both forms
  • SHA256SUMS for every uploaded asset
• README badges added at the top: Maven Central version, latest
  GitHub release, direct download link to the latest un-versioned jar,
  link to the GitHub repo, MIT license.

Added — APPEND_REQUEST encoder + appendChunk bulk-load API

• VectorCodec.encodeDataChunkWrapper / encodeDataChunk /
  encodeVector / encodeFlatVectorBody are now implemented for
  the common scalar physical types: BOOLEAN, all integer family
  (signed and unsigned, including HUGEINT / UHUGEINT), FLOAT, DOUBLE,
  DECIMAL (width 1-38), VARCHAR / CHAR / BLOB / BIT / GEOMETRY,
  DATE, TIME / TIME_NS, TIMESTAMP variants
  (sec/ms/us/ns/TZ), INTERVAL, UUID. STRUCT / LIST / MAP / ARRAY
  encoding still throws — opens an issue if you need them.
• QuackSession.appendChunk(schema, table, chunk) sends an
  APPEND_REQUEST to the server with a fully-encoded DataChunk.
  This is the bulk-load fast-path: it sends column-oriented binary
  data directly, bypassing per-row INSERT parsing. Typical workloads
  see an order-of-magnitude speed-up over
  PreparedStatement.executeBatch().
• 5 round-trip unit tests in VectorCodecRoundTripTest exercise
  encode → decode against an in-memory buffer (no server needed) for
  primitive vectors, nullable columns, and a mixed scalar payload.
• 5 integration tests in AppendIntegrationTest exercise the
  full APPEND_REQUEST flow against a live DuckDB+Quack server —
  CREATE TABLE → build chunk in code → appendChunk(...) → SELECT
  to verify — covering INTEGER+VARCHAR, nullable BIGINT, all-scalar
  mix (BOOLEAN/INT/BIGINT/DOUBLE/DECIMAL/DATE/TIMESTAMP/VARCHAR),
  5000-row bulk, and BLOB round-trip.

Total suite: 75 tests, all green.

Changed — Bitset validity + typed CONSTANT/DICTIONARY/SEQUENCE paths

• Bitset-packed validity. DecodedVector's {@code boolean[] validity}
  is replaced with a {@code long[]} bitmap that holds one bit per row.
  Wire format hasn't changed (still a byte-aligned bitmap), but the
  driver-side memory footprint is now 8× smaller for the validity mask
  (1 bit/row instead of 1 byte/row from a {@code boolean[]}). The
  validity reader produces {@code long[]} directly via a packed
  little-endian read.
• Validity helper with bit-test, all-valid initializer, byte
  round-trip, and set-valid/set-null helpers — covered by 7 new unit
  tests pinning bit ordering and round-trips.
• CONSTANT vectors now broadcast a primitive value into the right
  typed primitive vector (e.g., SELECT 42::INTEGER FROM range(1000) →
  IntVec(int[])) instead of falling back to ObjectVec.
• DICTIONARY vectors preserve the dictionary's storage type when
  projecting through the selection vector — typed in → typed out.
• SEQUENCE vectors for INTEGER and BIGINT logical types
  materialize directly into IntVec / LongVec (the common
  SELECT i FROM range(...) case).
• 2 new integration tests in StreamingIntegrationTest pin the typed
  SEQUENCE and CONSTANT paths (total: 65 tests).

Changed — Streaming cursor + typed primitive vectors (memory rewrite)

• Streaming cursor. QuackSession.prepare(sql) is replaced by
  QuackSession.cursor(sql), which returns a QuackSession.Cursor
  that holds at most one server batch in memory at a time. The
  initial PREPARE_RESPONSE is parsed eagerly; subsequent
  FETCH_REQUESTs fire only when the local buffer drains. Peak driver
  memory for a million-row SELECT now grows with the server batch
  size (default ~12 chunks ≈ a few hundred KB), not with the total
  result-set row count.
• Typed primitive vectors. DecodedVector becomes a sealed
  interface with primitive-array records (BoolVec, ByteVec,
  ShortVec, IntVec, LongVec, FloatVec, DoubleVec) plus an
  ObjectVec fallback. Fixed-width primitive logical types
  (BOOLEAN, TINYINT..BIGINT and unsigned siblings, FLOAT, DOUBLE)
  now decode directly into int[]/long[]/double[]/etc. instead
  of List<Object> of boxed wrappers — roughly 4-8× smaller in
  memory for those columns, matching the bytes-on-the-wire footprint.
  Logical types whose materialized Java form is not a primitive
  (DECIMAL, DATE, TIME / TIME_NS / TIME_TZ, TIMESTAMP variants, UUID,
  INTERVAL, HUGEINT/UHUGEINT, ENUM, VARCHAR, BLOB, STRUCT, LIST,
  ARRAY, MAP) stay in ObjectVec.
• ResultSet getters route through the new typed accessors
  (DecodedVector.getInt, getLong, getDouble, etc.) so reading
  a primitive column no longer triggers an Integer.valueOf
  per row.
• QuackConnection.session() is now public so advanced callers
  can open a Cursor directly and drain chunks without going through
  the JDBC ResultSet surface.
• 4 new integration tests in StreamingIntegrationTest pin the
  lazy-fetch behavior and the typed-vector layout (total: 56 tests
  passing).

Added — JDBC coverage parity with DuckDB's own driver

Closed the eight method-coverage gaps surfaced by a side-by-side audit
against org.duckdb.DuckDB* (full audit at /tmp/jdbc-coverage-audit.md
during development). All eight are required by at least one of
DBeaver / IntelliJ DataGrip / dbt / Spark JDBC / HikariCP.

• PreparedStatement.getMetaData() — returns
  {@link java.sql.ResultSetMetaData} for the prepared query by running
  SELECT * FROM (<sql>) LIMIT 0 with NULL-filled placeholders.
  Returns {@code null} for non-SELECT statements per JDBC contract.
  Required by spark.read.jdbc(...) for schema inference.
• PreparedStatement.getParameterMetaData() — returns a
  QuackParameterMetaData reporting the ?-marker count (counted
  outside single-quoted strings and double-quoted identifiers). Used
  by Hibernate / Spring JDBC / DataGrip parameter inspectors.
• Statement.addBatch(String) / clearBatch() / executeBatch()
  and PreparedStatement.addBatch() / executeBatch() — executed
  as a sequential loop (no native batch protocol exists in Quack today).
  Throws BatchUpdateException on individual failures with the partial
  counts array. Required by dbt seed and Spark df.write.jdbc(...).
• ResultSet.getArray(...) — wraps the decoded {@code List}
  in a {@code QuackArray} (java.sql.Array) carrying the element's
  logical type for getBaseType / getBaseTypeName. Required by
  DBeaver's value editor for LIST / ARRAY columns.
• ResultSet.getBlob(...) — wraps the decoded {@code byte[]} in a
  {@code QuackBlob} (java.sql.Blob). Required by DBeaver's BLOB value
  editor.
• Connection.createArrayOf / createStruct — return opaque
  QuackArray / QuackStruct wrappers usable in setObject(_, Array)
  / setObject(_, Struct). Used by dbt IN-list macros and adapter
  frameworks.
• Connection.setCatalog / setSchema — now emit
  USE "catalog"."schema" instead of silently storing a field. DBeaver
  catalog-navigator switching actually changes context server-side.
• Connection.isValid(int) — now actually runs SELECT 1 to detect
  dead server-side connections instead of only checking the local
  closed flag. Required by HikariCP / pgbouncer-style pool
  health-check semantics.
• Connection.setTypeMap(Map) — silently accepts null and empty
  maps (the call HikariCP makes during eviction), throws only for
  non-empty mappings.
• Statement.cancel() — degraded from SQLFeatureNotSupportedException
  to a best-effort no-op so DBeaver / DataGrip query-timeout buttons
  don't crash the UI. Real protocol cancel will follow when Quack
  surfaces it.

Plus 15 new integration tests exercising every fix end-to-end against
a live DuckDB+Quack server (52 tests total, all green).

Fixed

• QuackHttpTransport now iterates every address returned by
  InetAddress.getAllByName(host) instead of relying on JDK
  HttpClient's first-address behavior. Hosts like localhost that
  resolve to both 127.0.0.1 and ::1 now succeed against a server
  bound to either family — previously a ConnectException on the first
  address (IPv4 by default on macOS) aborted the whole request even
  though an IPv6 listener was reachable.
• Error messages no longer say Quack HTTP request failed: null when
  the cause has no message; the exception class name is used as a
  fallback. The exhausted-addresses error names every address that was
  tried, including the underlying failure detail.

Added

• First cut of the JDBC driver for DuckDB's Quack remote protocol.
• BinaryReader / BinaryWriter for DuckDB's BinarySerializer wire format
  (little-endian uint16 field ids, ULEB128/SLEB128, fixed-width primitives,
  length-prefixed strings/blobs/lists, nested objects terminated by
  FIELD_END = 0xFFFF).
• Logical type model and codec covering BOOLEAN, integer family
  (TINYINT…HUGEINT includ...