psycopg release notes

Future releases

Psycopg 3.2 (unreleased)

• Add support for integer, floating point, boolean NumPy scalar types (ticket #332).

• Add timeout and stop_after parameters to Connection.notifies() (ticket 340).

• Add Raw query cursors to execute queries using placeholders in PostgreSQL format ($1, $2…) (ticket #560).

• Add psycopg.capabilities object to inspect the libpq capabilities (ticket #772).

• Add scalar_row to return scalar values from a query (ticket #723).

• Prepared statements are now compatible with PgBouncer. (ticket #589).

• Add set_autocommit() on sync connections, and similar transaction control methods available on the async connections.

• Add support for libpq functions to close prepared statements and portals introduced in libpq v17 (ticket #603).

• Add support for libpq encrypted and non-blocking query cancellation functions introduced in libpq v17 (ticket #754).

• The context parameter of sql objects as_string() and as_bytes() methods is now optional (ticket #716).

• Disable receiving more than one result on the same cursor in pipeline mode, to iterate through nextset(). The behaviour was different than in non-pipeline mode and not totally reliable (ticket #604). The Cursor now only preserves the results set of the last execute(), consistently with non-pipeline mode.

• Add cancel_safe() for encrypted and non-blocking cancellation If possible, use such method internally upon KeyboardInterrupt and Copy termination (ticket #754).

• Add support for libpq function to retrieve results in chunks introduced in libpq v17 (ticket #793).

Psycopg 3.1.19 (unreleased)

• Fix unaligned access undefined behaviour in C extension (ticket #734).

• Fix excessive stripping of error message prefixes (ticket #752).

• Allow to specify the connect_timeout connection parameter as float (ticket #796).

Current release

Psycopg 3.1.18

• Fix possible deadlock on pipeline exit (ticket #685).

• Fix overflow loading large intervals in C module (ticket #719).

• Fix compatibility with musl libc distributions affected by CPython issue #65821 (ticket #725).

Psycopg 3.1.17

• Fix multiple connection attempts when a host name resolve to multiple IP addresses (ticket #699).

• Use typing.Self as a more correct return value annotation of context managers and other self-returning methods (see ticket #708).

Psycopg 3.1.16

• Fix empty ports handling in async multiple connection attempts (ticket #703).

Psycopg 3.1.15

• Fix use of service in connection string (regression in 3.1.13, ticket #694).

• Fix async connection to hosts resolving to multiple IP addresses (regression in 3.1.13, ticket #695).

• Respect the PGCONNECT_TIMEOUT environment variable to determine the connection timeout.

Psycopg 3.1.14

• Fix interaction with gevent (ticket #527).

• Add support for PyPy (ticket #686).

Psycopg 3.1.13

• Raise DataError instead of whatever internal failure trying to dump a time object with with a tzinfo specified as ZoneInfo (ambiguous offset, see ticket #652).

• Handle gracefully EINTR on signals instead of raising InterruptedError, consistently with PEP 475 guideline (ticket #667).

• Fix support for connection strings with multiple hosts/ports and for the load_balance_hosts connection parameter (ticket #674).

• Fix memory leak receiving notifications in Python implementation (ticket #679).

Psycopg 3.1.12

• Fix possible hanging if a connection is closed while querying (ticket #608).

• Fix memory leak when register_*() functions are called repeatedly (ticket #647).

• Release Python 3.12 binary packages.

Psycopg 3.1.11

• Avoid caching the parsing results of large queries to avoid excessive memory usage (ticket #628).

• Fix integer overflow in C/binary extension with OID > 2^31 (ticket #630).

• Fix loading of intervals with days and months or years (ticket #643).

• Work around excessive CPU usage on Windows (reported in ticket #645).

• Fix building on Solaris and derivatives (ticket #632).

• Fix possible lack of critical section guard in async executemany().

• Fix missing pipeline fetch in async scroll().

• Build binary packages with libpq 15.4, which allows group-readable permissions on the SSL certificate on the client (ticket #528).

Psycopg 3.1.10

• Allow JSON dumpers to dump bytes directly instead of str, for better compatibility with libraries like orjson and msgspec (ticket #569)

• Fix prepared statement cache validation when exiting pipeline mode (or executemany()) in case an error occurred within the pipeline (ticket #585).

• Fix connect() to avoid “leaking” an open PGconn attached to the OperationalError in case of connection failure. Error.pgconn is now a shallow copy of the real libpq connection, and the latter is closed before the exception propagates (ticket #565).

• Fix possible (ignored) exception on objects deletion (ticket #591).

• Don’t clobber a Python exception raised during COPY FROM with the resulting QueryCanceled raised as a consequence (ticket #593).

• Fix resetting Connection.read_only and deferrable to their default value using None (ticket #612).

• Add support for Python 3.12.

Psycopg 3.1.9

• Fix TypeInfo.fetch() using a connection in sql_ascii encoding (ticket #503).

• Fix “filedescriptor out of range” using a large number of files open in Python implementation (ticket #532).

• Allow JSON dumpers to be registered on dict or any other object, as was possible in psycopg2 (ticket #541).

• Fix canceling running queries on process interruption in async connections (ticket #543).

• Fix loading ROW values with different types in the same query using the binary protocol (ticket #545).

• Fix dumping recursive composite types (ticket #547).

Psycopg 3.1.8

• Don’t pollute server logs when types looked for by TypeInfo.fetch() are not found (ticket #473).

• Set Cursor.rowcount to the number of rows of each result set from executemany() when called with returning=True (ticket #479).

• Fix TypeInfo.fetch() when used with ClientCursor (ticket #484).

Psycopg 3.1.7

• Fix server-side cursors using row factories (ticket #464).

Psycopg 3.1.6

• Fix cursor.copy() with cursors using row factories (ticket #460).

Psycopg 3.1.5

• Fix array loading slowness compared to psycopg2 (ticket #359).

• Improve performance around network communication (ticket #414).

• Return bytes instead of memoryview from pq.Encoding methods (ticket #422).

• Fix Cursor.rownumber to return None when the result has no row to fetch (ticket #437).

• Avoid error in Pyright caused by aliasing TypeAlias (ticket #439).

• Fix Copy.set_types() used with varchar and name types (ticket #452).

• Improve performance using Row factories (ticket #457).

Psycopg 3.1.4

• Include error classes defined in PostgreSQL 15.

• Add support for Python 3.11 (ticket #305).

• Build binary packages with libpq from PostgreSQL 15.0.

Psycopg 3.1.3

• Restore the state of the connection if Cursor.stream() is terminated prematurely (ticket #382).

• Fix regression introduced in 3.1 with different named tuples mangling rules for non-ascii attribute names (ticket #386).

• Fix handling of queries with escaped percent signs (%%) in ClientCursor (ticket #399).

• Fix possible duplicated BEGIN statements emitted in pipeline mode (ticket #401).

Psycopg 3.1.2

• Fix handling of certain invalid time zones causing problems on Windows (ticket #371).

• Fix segfault occurring when a loader fails initialization (ticket #372).

• Fix invalid SAVEPOINT issued when entering Connection.transaction() within a pipeline using an implicit transaction (ticket #374).

• Fix queries with repeated named parameters in ClientCursor (ticket #378).

• Distribute macOS arm64 (Apple M1) binary packages (ticket #344).

Psycopg 3.1.1

• Work around broken Homebrew installation of the libpq in a non-standard path (ticket #364)

• Fix possible “unrecognized service” error in async connection when no port is specified (ticket #366).

Psycopg 3.1

• Add Pipeline mode (ticket #74).

• Add Client-side-binding cursors (ticket #101).

• Add CockroachDB support in psycopg.crdb (ticket #313).

• Add Two-Phase Commit support (ticket #72).

• Add Enum adaptation (ticket #274).

• Add returning parameter to executemany() to retrieve query results (ticket #164).

• executemany() performance improved by using batch mode internally (ticket #145).

• Add parameters to copy().

• Add COPY Writer objects.

• Resolve domain names asynchronously in AsyncConnection.connect() (ticket #259).

• Add pq.PGconn.trace() and related trace functions (ticket #167).

• Add prepare_threshold parameter to Connection init (ticket #200).

• Add cursor_factory parameter to Connection init.

• Add Error.pgconn and Error.pgresult attributes (ticket #242).

• Restrict queries to be LiteralString as per PEP 675 (ticket #323).

• Add explicit type cast to values converted by sql.Literal (ticket #205).

• Drop support for Python 3.6.

Psycopg 3.0.17

• Fix segfaults on fork on some Linux systems using ctypes implementation (ticket #300).

• Load bytea as bytes, not memoryview, using ctypes implementation.

Psycopg 3.0.16

• Fix missing rowcount after SHOW (ticket #343).

• Add scripts to build macOS arm64 packages (ticket #162).

Psycopg 3.0.15

• Fix wrong escaping of unprintable chars in COPY (nonetheless correctly interpreted by PostgreSQL).

• Restore the connection to usable state after an error in stream().

• Raise DataError instead of OverflowError loading binary intervals out-of-range.

• Distribute manylinux2014 wheel packages (ticket #124).

Psycopg 3.0.14

• Raise DataError dumping arrays of mixed types (ticket #301).

• Fix handling of incorrect server results, with blank sqlstate (ticket #303).

• Fix bad Float4 conversion on ppc64le/musllinux (ticket #304).

Psycopg 3.0.13

• Fix Cursor.stream() slowness (ticket #286).

• Fix oid for lists of integers, which might cause the server choosing bad plans (ticket #293).

• Make Connection.cancel() on a closed connection a no-op instead of an error.

Psycopg 3.0.12

• Allow bytearray/memoryview data too as Copy.write() input (ticket #254).

• Fix dumping IntEnum in text mode, Python implementation.

Psycopg 3.0.11

• Fix DataError loading arrays with dimensions information (ticket #253).

• Fix hanging during COPY in case of memory error (ticket #255).

• Fix error propagation from COPY worker thread (mentioned in ticket #255).

Psycopg 3.0.10

• Leave the connection in working state after interrupting a query with Ctrl-C (ticket #231).

• Fix Cursor.description after a COPY … TO STDOUT operation (ticket #235).

• Fix building on FreeBSD and likely other BSD flavours (ticket #241).

Psycopg 3.0.9

• Set Error.sqlstate when an unknown code is received (ticket #225).

• Add the tzdata package as a dependency on Windows in order to handle time zones (ticket #223).

Psycopg 3.0.8

• Decode connection errors in the client_encoding specified in the connection string, if available (ticket #194).

• Fix possible warnings in objects deletion on interpreter shutdown (ticket #198).

• Don’t leave connections in ACTIVE state in case of error during COPY … TO STDOUT (ticket #203).

Psycopg 3.0.7

• Fix crash in executemany() with no input sequence (ticket #179).

• Fix wrong rowcount after an executemany() returning no rows (ticket #178).

Psycopg 3.0.6

• Allow to use Cursor.description if the connection is closed (ticket #172).

• Don’t raise exceptions on ServerCursor.close() if the connection is closed (ticket #173).

• Fail on Connection.cursor() if the connection is closed (ticket #174).

• Raise ProgrammingError if out-of-order exit from transaction contexts is detected (tickets #176, #177).

• Add CHECK_STANDBY value to ConnStatus enum.

Psycopg 3.0.5

• Fix possible “Too many open files” OS error, reported on macOS but possible on other platforms too (ticket #158).

• Don’t clobber exceptions if a transaction block exit with error and rollback fails (ticket #165).

Psycopg 3.0.4

• Allow to use the module with strict strings comparison (ticket #147).

• Fix segfault on Python 3.6 running in -W error mode, related to backport.zoneinfo ticket #109.

• Build binary package with libpq versions not affected by CVE-2021-23222 (ticket #149).

Psycopg 3.0.3

• Release musllinux binary packages, compatible with Alpine Linux (ticket #141).

• Reduce size of binary package by stripping debug symbols (ticket #142).

• Include typing information in the psycopg_binary package.

Psycopg 3.0.2

• Fix type hint for sql.SQL.join() (ticket #127).

• Fix type hint for Connection.notifies() (ticket #128).

• Fix call to MultiRange.__setitem__() with a non-iterable value and a slice, now raising a TypeError (ticket #129).

• Fix disable cursors methods after close() (ticket #125).

Psycopg 3.0.1

• Fix use of the wrong dumper reusing cursors with the same query but different parameter types (ticket #112).

Psycopg 3.0

First stable release. Changed from 3.0b1:

• Add Geometry adaptation using Shapely (ticket #80).

• Add Multirange adaptation (ticket #75).

• Add pq.__build_version__ constant.

• Don’t use the extended protocol with COPY, (tickets #78, #82).

• Add context parameter to connect() (ticket #83).

• Fix selection of dumper by oid after set_types().

• Drop Connection.client_encoding. Use ConnectionInfo.encoding to read it, and a SET statement to change it.

• Add binary packages for Python 3.10 (ticket #103).

Psycopg 3.0b1

• First public release on PyPI.