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# name: test/sql/storage/compression/bitpacking/bitpacking_compression_ratio.test_slow
# description: Assert bitpacking compression ratio is within reasonable margins for each mode
# group: [bitpacking]
# This test defaults to another compression function for smaller block sizes,
# because the bitpacking groups no longer fit the blocks.
require block_size 262144
load __TEST_DIR__/test_bitpacking.db
#### CONSTANT MODE Compression ratio calculation:
# For single row group (note we choose values such that we don't create the constant segments):
# 59 vectors with CONSTANT mode, the last one will be FOR mode
# Total compressed bytes = 59*(8+4) + 1*(2048/8 + 8 + 8 + 4) = 984
# Total uncompressed bytes = 120000*8 = 960000
# Ratio ~= 975x
# However, because this completely fills up a block and we do not support block sharing yet, we waste a lot of space
statement ok
PRAGMA force_compression='bitpacking'
statement ok
PRAGMA force_bitpacking_mode='constant'
statement ok
CREATE TABLE test_bitpacked AS SELECT (i//119000::INT64)::INT64 AS i FROM range(0, 120000000) tbl(i);
statement ok
checkpoint
statement ok
PRAGMA force_compression='uncompressed'
statement ok
CREATE TABLE test_uncompressed AS SELECT i::INT64 FROM range(0, 120000000) tbl(i);
statement ok
checkpoint
query I
SELECT compression FROM pragma_storage_info('test_bitpacked') WHERE segment_type != 'VALIDITY' AND compression != 'BitPacking';
----
query I
SELECT compression FROM pragma_storage_info('test_uncompressed') WHERE segment_type != 'VALIDITY' AND compression != 'Uncompressed';
----
query II
select (uncompressed::FLOAT / bitpacked::FLOAT) > 700, (uncompressed::FLOAT / bitpacked::FLOAT) < 1000 FROM (
select
(select count(distinct block_id) from pragma_storage_info('test_bitpacked') where segment_type not in('VARCHAR', 'VALIDITY')) as bitpacked,
(select count(distinct block_id) from pragma_storage_info('test_uncompressed') where segment_type not in('VARCHAR', 'VALIDITY')) as uncompressed
)
----
True True
statement ok
drop table test_bitpacked;
drop table test_uncompressed;
#### CONSTANT DELTA MODE Compression ratio calculation:
# For single row group
# 60 vectors with a constant increase (1)
# Total compressed bytes = 60*(8+8+4) = 1200
# Total uncompressed bytes = 120000*8 = 960000
# Expected Ratio ~= 800x
statement ok
PRAGMA force_compression='bitpacking'
statement ok
PRAGMA force_bitpacking_mode='constant_delta'
statement ok
CREATE TABLE test_bitpacked AS SELECT i::INT64 AS i FROM range(0, 120000000) tbl(i);
statement ok
checkpoint
statement ok
PRAGMA force_compression='uncompressed'
statement ok
CREATE TABLE test_uncompressed AS SELECT i::INT64 AS i FROM range(0, 120000000) tbl(i);
statement ok
checkpoint
query I
SELECT compression FROM pragma_storage_info('test_bitpacked') WHERE segment_type != 'VALIDITY' AND compression != 'BitPacking';
----
query I
SELECT compression FROM pragma_storage_info('test_uncompressed') WHERE segment_type != 'VALIDITY' AND compression != 'Uncompressed';
----
statement ok
checkpoint
query II
select (uncompressed::FLOAT / bitpacked::FLOAT) > 600, (uncompressed::FLOAT / bitpacked::FLOAT) < 800 FROM (
select
(select count(distinct block_id) from pragma_storage_info('test_bitpacked') where segment_type not in('VARCHAR', 'VALIDITY')) as bitpacked,
(select count(distinct block_id) from pragma_storage_info('test_uncompressed') where segment_type not in('VARCHAR', 'VALIDITY')) as uncompressed
)
----
True True
statement ok
drop table test_bitpacked;
drop table test_uncompressed;
#### DELTA FOR MODE Compression ratio calculation:
# For single row group
# 60 vectors with DELTA_FOR mode smallest possible compression
# Total compressed bytes = 60*(8+8+4+(2048/8)) = 16560
# Total uncompressed bytes = 120000*8 = 960000
# Expected Ratio ~= 58x
statement ok
PRAGMA force_compression='bitpacking'
statement ok
PRAGMA force_bitpacking_mode='delta_for'
statement ok
CREATE TABLE test_bitpacked AS SELECT i//2::INT64 AS i FROM range(0, 120000000) tbl(i);
statement ok
checkpoint
statement ok
PRAGMA force_compression='uncompressed'
statement ok
CREATE TABLE test_uncompressed AS SELECT i AS i FROM range(0, 120000000) tbl(i);
statement ok
checkpoint
query I
SELECT compression FROM pragma_storage_info('test_bitpacked') WHERE segment_type != 'VALIDITY' AND compression != 'BitPacking';
----
query I
SELECT compression FROM pragma_storage_info('test_uncompressed') WHERE segment_type != 'VALIDITY' AND compression != 'Uncompressed';
----
statement ok
checkpoint
query II
select (uncompressed::FLOAT / bitpacked::FLOAT) > 50, (uncompressed::FLOAT / bitpacked::FLOAT) < 60 FROM (
select
(select count(distinct block_id) from pragma_storage_info('test_bitpacked') where segment_type not in('VARCHAR', 'VALIDITY')) as bitpacked,
(select count(distinct block_id) from pragma_storage_info('test_uncompressed') where segment_type not in('VARCHAR', 'VALIDITY')) as uncompressed
)
----
True True
statement ok
drop table test_bitpacked;
drop table test_uncompressed;
# FOR MODE Compression ratio calculation:
# For single row group
# 60 vectors with DELTA_FOR mode smallest possible compression
# Total compressed bytes = 60*(8+4+(2048/8)) = 16080
# Total uncompressed bytes = 120000*8 = 960000
# Expected Ratio ~= 60x
statement ok
PRAGMA force_compression='bitpacking'
statement ok
PRAGMA force_bitpacking_mode='for'
statement ok
CREATE TABLE test_bitpacked AS SELECT i%2::INT64 AS i FROM range(0, 120000000) tbl(i);
statement ok
checkpoint
statement ok
PRAGMA force_compression='uncompressed'
statement ok
CREATE TABLE test_uncompressed AS SELECT i::INT64 AS i FROM range(0, 120000000) tbl(i);
statement ok
checkpoint
query I
SELECT compression FROM pragma_storage_info('test_bitpacked') WHERE segment_type != 'VALIDITY' AND compression != 'BitPacking';
----
query I
SELECT compression FROM pragma_storage_info('test_uncompressed') WHERE segment_type != 'VALIDITY' AND compression != 'Uncompressed';
----
statement ok
checkpoint
query II
select (uncompressed::FLOAT / bitpacked::FLOAT) > 50, (uncompressed::FLOAT / bitpacked::FLOAT) < 60 FROM (
select
(select count(distinct block_id) from pragma_storage_info('test_bitpacked') where segment_type not in('VARCHAR', 'VALIDITY')) as bitpacked,
(select count(distinct block_id) from pragma_storage_info('test_uncompressed') where segment_type not in('VARCHAR', 'VALIDITY')) as uncompressed
)
----
True True
statement ok
drop table test_bitpacked;
drop table test_uncompressed;
statement ok
PRAGMA force_bitpacking_mode='auto'
# Assert that all supported types do in fact compress
foreach type int8 int16 int32 int64 uint8 uint16 uint32 uint64 decimal(4,1) decimal(8,1) decimal(12,1) decimal(18,1) bool
statement ok
PRAGMA force_compression='uncompressed';
statement ok
CREATE TABLE test_uncompressed AS SELECT (i%2)::${type} FROM range(0, 2500000) tbl(i);
statement ok
checkpoint
statement ok
PRAGMA force_compression='bitpacking'
statement ok
CREATE TABLE test_bitpacked AS SELECT (i%2)::${type} FROM range(0, 2500000) tbl(i);
statement ok
checkpoint
# assert compression ratio >2 wich should be achieved for even the smallest types for this data
query II
select (uncompressed::FLOAT / bitpacked::FLOAT) > 2, CAST(1 as ${type}) FROM (
select
(select count(distinct block_id) from pragma_storage_info('test_bitpacked') where segment_type not in('VARCHAR', 'VALIDITY')) as bitpacked,
(select count(distinct block_id) from pragma_storage_info('test_uncompressed') where segment_type not in('VARCHAR', 'VALIDITY')) as uncompressed
)
----
1 1
statement ok
drop table test_bitpacked
statement ok
drop table test_uncompressed
endloop
|
