The functions for adding and updating dimensions have been refactored
in C to:
- improve usage of proper error codes
- make messages that better conform with the PostgreSQL standard.
- improve security by avoiding that lots of code run under SECURITY DEFINER
A new if_not_exists option has also been added to add_dimension() and
a the number of partitions can now be set using the new
set_number_partitions() function.
A bug in the validation of smallint time intervals has been fixed. The
previous code didn't check for intervals > 0 and smallint intervals
accepted values up to UINT16_MAX instead of INT16_MAX.
This PR adds the ability to have multiple different versions of the timescaledb
extension be used by different databases in the same PostgreSQL
instance (server).
This is accomplished by splitting this extension into two .so files.
1) timescaledb.so -- stuff under loader/. Really not a lot of code.
This code MUST be backwards compatible in the future.
2) timescaledb-version.so (most of our code). Need
not be backwards compatible.
Timescaledb.so becomes a small stub which is preloaded and whose main
reason for existing is to dynamically load the right
timescaledb-version.so when the time comes.
This change allows either of the above .so to be loaded in
shared_preload_libraries. But timescaledb.so allows for multiple
versions used on different databases in the same instance along
with smoother upgrades. Using timescaledb-version.so allows for
finer-grained control and lock-in and is appropriate in only a few
production environments.
This PR also adds version checking so that a clear failure message
will be displayed if the .so version does not match the SQL extension
version.
To support multi-version functionality we changed the way SQL update
scripts are generated. Previously, the system used a bunch of
intermediate upgrade scripts. So with 3 versions, you would have an
update script of 1--2, 2--3. But, this PR changes things so that we
produce direct "shortcut" update files: 1--3, 2--3.
This is done for 2 reasons:
1) Each of the update files should point to
$libdir/timescaledb-current_version. Since you cannot guarantee that
Previous .so for each intermediate version has been installed.
2) You don't want intermediate version updates installed without the
.so. For example, if you have versions 1,2,3
and you are installing version 3, you want the upgrade files 1--3,
2--3 but not 1--2 because if you have 1--2
then a user could do ALTER EXTENSION timescaledb UPDATE TO 2. But
the .so for version 2 may not be installed.
In order to test this functionality, we add a mock extension version .so
that we can test extension loading inside the regression framework.
The user should be able to add time dimensions using INTERVAL when
the column type is TIMESTAMP/TIMESTAMPTZ/DATE, so this change adds
that support.
Additionally it adds some additional tests and checks for
add_dimension, e.g., a nice error when the table is not a
hypertable.
reindex allows you to reindex the indexes of only certain chunks,
filtering by time. This is a common use case because a user may
want to reindex chunks after they are no longer getting new data once.
reindex also has a recreate option which will not use REINDEX
but will rather CREATE INDEX a new index and then
DROP INDEX / RENAME new_index to old_name. This approach has advantages
in terms of blocking reads for a much shorter period of time. However,
it does more work and will use more disk space during the operation.
Previously, for timezones w/o tz. The range_end and range_start were
defined as UTC, but the constraints on the table were written as as
the local time at the time of chunk creation. This does not work well
if timezones change over the life of the hypertable.
This change removes the dependency on local time for all timestamp
partitioning. Namely, the range_start and range_end remain as UTC
but the constraints are now always written in UTC too. Since old
constraints correctly describe the data currently in the chunks, the
update script to handle this change changes range_start and range_end
instead of the constraints.
Fixes#300.
Functions marked IMMUTABLE should also be parallel safe, but
aren't by default. This change marks all immutable functions
as parallel safe and removes the IMMUTABLE definitions on
some functions that have been wrongly labeled as IMMUTABLE.
If functions that are IMMUTABLE does not have the PARALLEL SAFE
label, then some standard PostgreSQL regression tests will fail
(this is true for PostgreSQL >= 10).
Clean up the table schema to get rid of legacy tables and functionality
that makes it more difficult to provide an upgrade path.
Notable changes:
* Get rid of legacy tables and code
* Simplify directory structure for SQL code
* Simplify table hierarchy: remove root table and make chunk tables
* inherit directly from main table
* Change chunk table suffix from _data to _chunk
* Simplify schema usage: _timescaledb_internal for internal functions.
* _timescaledb_catalog for metadata tables.
* Remove postgres_fdw dependency
* Improve code comments in sql code
