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6d78e3be94
* Function to check if given token is present in a string; * Special case for hasToken to 'tokenbf_v1' index; * Test cases for hasToken() * Test case for hasToken() + 'tokenbf_v1' integration
33 lines
1.2 KiB
SQL
33 lines
1.2 KiB
SQL
SET allow_experimental_data_skipping_indices = 1;
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DROP TABLE IF EXISTS bloom_filter;
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CREATE TABLE bloom_filter
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(
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id UInt64,
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s String,
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INDEX tok_bf (s, lower(s)) TYPE tokenbf_v1(512, 3, 0) GRANULARITY 1
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) ENGINE = MergeTree() ORDER BY id SETTINGS index_granularity = 8;
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insert into bloom_filter select number, 'yyy,uuu' from numbers(1024);
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insert into bloom_filter select number+2000, 'abc,def,zzz' from numbers(8);
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insert into bloom_filter select number+3000, 'yyy,uuu' from numbers(1024);
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insert into bloom_filter select number+3000, 'abcdefzzz' from numbers(1024);
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set max_rows_to_read = 16;
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SELECT max(id) FROM bloom_filter WHERE hasToken(s, 'abc');
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SELECT max(id) FROM bloom_filter WHERE hasToken(s, 'def');
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SELECT max(id) FROM bloom_filter WHERE hasToken(s, 'zzz');
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-- invert result
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-- this does not work as expected, reading more rows that it should
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-- SELECT max(id) FROM bloom_filter WHERE NOT hasToken(s, 'yyy');
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-- accessing to many rows
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SELECT max(id) FROM bloom_filter WHERE hasToken(s, 'yyy'); -- { serverError 158 }
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-- this syntax is not supported by tokenbf
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SELECT max(id) FROM bloom_filter WHERE hasToken(s, 'zzz') == 1; -- { serverError 158 }
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DROP TABLE bloom_filter; |