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114 lines
2.8 KiB
Plaintext
114 lines
2.8 KiB
Plaintext
SET enable_seqscan = off;
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-- L2
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CREATE TABLE t (val halfvec(3));
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INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
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CREATE INDEX ON t USING ivfflat (val halfvec_l2_ops) WITH (lists = 1);
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INSERT INTO t (val) VALUES ('[1,2,4]');
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SELECT * FROM t ORDER BY val <-> '[3,3,3]';
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val
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---------
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[1,2,3]
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[1,2,4]
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[1,1,1]
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[0,0,0]
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(4 rows)
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SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <-> (SELECT NULL::halfvec)) t2;
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count
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-------
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4
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(1 row)
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SELECT COUNT(*) FROM t;
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count
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-------
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5
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(1 row)
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TRUNCATE t;
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NOTICE: ivfflat index created with little data
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DETAIL: This will cause low recall.
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HINT: Drop the index until the table has more data.
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SELECT * FROM t ORDER BY val <-> '[3,3,3]';
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val
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-----
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(0 rows)
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DROP TABLE t;
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-- inner product
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CREATE TABLE t (val halfvec(3));
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INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
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CREATE INDEX ON t USING ivfflat (val halfvec_ip_ops) WITH (lists = 1);
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INSERT INTO t (val) VALUES ('[1,2,4]');
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SELECT * FROM t ORDER BY val <#> '[3,3,3]';
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val
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---------
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[1,2,4]
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[1,2,3]
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[1,1,1]
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[0,0,0]
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(4 rows)
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SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <#> (SELECT NULL::halfvec)) t2;
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count
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-------
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4
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(1 row)
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DROP TABLE t;
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-- cosine
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CREATE TABLE t (val halfvec(3));
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INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
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CREATE INDEX ON t USING ivfflat (val halfvec_cosine_ops) WITH (lists = 1);
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INSERT INTO t (val) VALUES ('[1,2,4]');
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SELECT * FROM t ORDER BY val <=> '[3,3,3]';
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val
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---------
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[1,1,1]
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[1,2,3]
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[1,2,4]
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(3 rows)
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SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <=> '[0,0,0]') t2;
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count
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-------
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3
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(1 row)
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SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <=> (SELECT NULL::halfvec)) t2;
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count
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-------
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3
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(1 row)
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DROP TABLE t;
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-- dimensions
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CREATE TABLE t (val halfvec(4000));
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CREATE INDEX ON t USING ivfflat (val halfvec_l2_ops);
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NOTICE: ivfflat index created with little data
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DETAIL: This will cause low recall.
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HINT: Drop the index until the table has more data.
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DROP TABLE t;
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CREATE TABLE t (val halfvec(4001));
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CREATE INDEX ON t USING ivfflat (val halfvec_l2_ops);
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ERROR: column cannot have more than 4000 dimensions for ivfflat index
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DROP TABLE t;
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-- memory
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SET maintenance_work_mem = '1MB';
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CREATE TABLE t (val halfvec(4000));
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CREATE INDEX ON t USING ivfflat (val halfvec_l2_ops);
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NOTICE: ivfflat index created with little data
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DETAIL: This will cause low recall.
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HINT: Drop the index until the table has more data.
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DROP TABLE t;
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RESET maintenance_work_mem;
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SET maintenance_work_mem = '6MB';
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CREATE TABLE t (val halfvec(4000));
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INSERT INTO t (val) VALUES (array_fill(0, ARRAY[4000]));
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CREATE INDEX ON t USING ivfflat (val halfvec_l2_ops);
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NOTICE: ivfflat index created with little data
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DETAIL: This will cause low recall.
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HINT: Drop the index until the table has more data.
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DROP TABLE t;
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RESET maintenance_work_mem;
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