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35 lines
1.8 KiB
SQL
35 lines
1.8 KiB
SQL
drop table if exists tab;
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create table tab (date Date, x UInt64, s FixedString(128)) engine = MergeTree(date, (date, x), 8192);
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insert into tab select today(), number, toFixedString('', 128) from system.numbers limit 8192;
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set preferred_block_size_bytes = 2000000;
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set preferred_max_column_in_block_size_bytes = 0;
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select max(blockSize()), min(blockSize()), any(ignore(*)) from tab;
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set preferred_max_column_in_block_size_bytes = 128;
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select max(blockSize()), min(blockSize()), any(ignore(*)) from tab;
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set preferred_max_column_in_block_size_bytes = 256;
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select max(blockSize()), min(blockSize()), any(ignore(*)) from tab;
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set preferred_max_column_in_block_size_bytes = 2097152;
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select max(blockSize()), min(blockSize()), any(ignore(*)) from tab;
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set preferred_max_column_in_block_size_bytes = 4194304;
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select max(blockSize()), min(blockSize()), any(ignore(*)) from tab;
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drop table if exists tab;
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create table tab (date Date, x UInt64, s FixedString(128)) engine = MergeTree(date, (date, x), 32);
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insert into tab select today(), number, toFixedString('', 128) from system.numbers limit 47;
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set preferred_max_column_in_block_size_bytes = 1152;
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select blockSize(), * from tab where x = 1 or x > 36 format Null;
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drop table if exists tab;
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create table tab (date Date, x UInt64, s FixedString(128)) engine = MergeTree(date, (date, x), 8192);
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insert into tab select today(), number, toFixedString('', 128) from system.numbers limit 10;
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set preferred_max_column_in_block_size_bytes = 128;
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select s from tab where s == '' format Null;
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drop table if exists tab;
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create table tab (date Date, x UInt64, s String) engine = MergeTree(date, (date, x), 8192);
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insert into tab select today(), number, 'abc' from system.numbers limit 81920;
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set preferred_block_size_bytes = 0;
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select count(*) from tab prewhere s != 'abc' format Null;
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select count(*) from tab prewhere s = 'abc' format Null;
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