Some small improvements:
- allow alter table with empty segment by if the original definition
had an empty segment by. Improve error msgs.
- block compression on tables with OIDs
- block compression on tables with RLS
Block most DDL commands on hypertables with compression enabled.
This restriction will be relaxed over time.
The only alter table commands currently allowed are:
Add/Remove index, Set storage options, clustering index,
set statistics and set tablespace.
We also disallow reseting compression options.
Primary and unqiue constraints are limited to segment_by and order_by
columns and foreign key constraints are limited to segment_by columns
when creating a compressed hypertable. There are no restrictions on
check constraints.
This simplifies the code and the access to the min/max
metadata. Before we used a custom type, but now the min/max
are just the same type as the underlying column and stored as two
columns.
This also removes the custom type that was used before.
- Fix declaration of functions wrt TSDLLEXPORT consistency
- Empty structs need to be created with '{ 0 }' syntax.
- Alignment sentinels have to use uint64 instead of a struct
with a 0-size member
- Add some more ORDER BY clauses in the tests to constrain
the order of results
- Add ANALYZE after running compression in
transparent-decompression test
Add drop policy can only be added to the public uncompressed hypertable.
This blocks a call when a policy is added to the internal
hypertable with compressed data.
This commit add handling for dropping of chunks and hypertables
in the presence of associated compressed objects. If the uncompressed
chunk/hypertable is dropped than drop the associated compressed object
using DROP_RESTRICT unless cascading is explicitly enabled.
Also add a compressed_chunk_id index on compressed tables for
figuring out whether a chunk is compressed or not.
Change a bunch of APIs to use DropBehavior instead of a cascade bool
to be more explicit.
Also test the drop chunks policy.
Add the column to the order by list if it's not already there.
This is never wrong and might improve performance. This
also guarantees that we have at least one ordering column
during compression and therefore can always use tuplesort
(o/w we'd need a non-tuplesort method of getting tuples).
Replace custom parsing of order by and segment by lists
with the postgres parser. The segment by list is now
parsed in the same way as the GROUP BY clause and the
order by list in the same way as the ORDER BY clause.
Also fix default for nulls first/last to follow the PG
convention: LAST for ASC, FIRST for DESC.
This is useful, if some or all compressed columns are NULL.
The count reflects the number of uncompressed rows that are
in the compressed row. Stored as a 32-bit integer.
Add support for compress_chunks function.
This also adds support for compress_orderby and compress_segmentby
parameters in ALTER TABLE. These parameteres are used by the
compress_chunks function.
The parsing code will most likely be changed to use PG raw_parser
function.
