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82 lines
3.4 KiB
SQL
82 lines
3.4 KiB
SQL
-- Tags: no-parallel
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drop table if exists pr_t;
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drop table if exists dist_pr_t;
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drop table if exists dist_t_different_dbs;
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drop table if exists shard_1.t_different_dbs;
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drop table if exists t_different_dbs;
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drop table if exists dist_t;
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drop table if exists t;
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create table t(a UInt64, b UInt64) engine=MergeTree order by a;
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system stop merges t;
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insert into t select number, number from numbers_mt(1e6);
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set enable_memory_bound_merging_of_aggregation_results = 1;
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set max_threads = 4;
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set optimize_aggregation_in_order = 1;
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set prefer_localhost_replica = 1;
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-- slightly different transforms will be generated by reading steps if we let settings randomisation to change this setting value --
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set read_in_order_two_level_merge_threshold = 1000;
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create table dist_t as t engine = Distributed(test_cluster_two_shards, currentDatabase(), t, a % 2);
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-- { echoOn } --
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explain pipeline select a from remote(test_cluster_two_shards, currentDatabase(), t) group by a;
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select a from remote(test_cluster_two_shards, currentDatabase(), t) group by a order by a limit 5 offset 100500;
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explain pipeline select a from remote(test_cluster_two_shards, currentDatabase(), dist_t) group by a;
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select a from remote(test_cluster_two_shards, currentDatabase(), dist_t) group by a order by a limit 5 offset 100500;
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-- { echoOff } --
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set aggregation_in_order_max_block_bytes = '1Mi';
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set max_block_size = 500;
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-- actual block size might be slightly bigger than the limit --
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select max(bs) < 70000 from (select avg(a), max(blockSize()) as bs from remote(test_cluster_two_shards, currentDatabase(), t) group by a);
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-- beautiful case when we have different sorting key definitions in tables involved in distributed query => different plans => different sorting properties of local aggregation results --
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create database if not exists shard_1;
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create table t_different_dbs(a UInt64, b UInt64) engine = MergeTree order by a;
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create table shard_1.t_different_dbs(a UInt64, b UInt64) engine = MergeTree order by tuple();
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insert into t_different_dbs select number % 1000, number % 1000 from numbers_mt(1e6);
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insert into shard_1.t_different_dbs select number % 1000, number % 1000 from numbers_mt(1e6);
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create table dist_t_different_dbs as t engine = Distributed(test_cluster_two_shards_different_databases_with_local, '', t_different_dbs);
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-- { echoOn } --
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explain pipeline select a, count() from dist_t_different_dbs group by a order by a limit 5 offset 500;
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select a, count() from dist_t_different_dbs group by a order by a limit 5 offset 500;
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select a, count() from dist_t_different_dbs group by a, b order by a limit 5 offset 500;
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-- { echoOff } --
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set allow_experimental_parallel_reading_from_replicas = 1;
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set max_parallel_replicas = 3;
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set use_hedged_requests = 0;
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create table pr_t(a UInt64, b UInt64) engine=MergeTree order by a;
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insert into pr_t select number % 1000, number % 1000 from numbers_mt(1e6);
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create table dist_pr_t as pr_t engine = Distributed(test_cluster_one_shard_three_replicas_localhost, currentDatabase(), pr_t);
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-- { echoOn } --
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explain pipeline select a from dist_pr_t group by a order by a limit 5 offset 500;
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select a, count() from dist_pr_t group by a order by a limit 5 offset 500;
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select a, count() from dist_pr_t group by a, b order by a limit 5 offset 500;
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-- { echoOff } --
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drop table pr_t;
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drop table dist_pr_t;
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drop table dist_t_different_dbs;
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drop table shard_1.t_different_dbs;
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drop table t_different_dbs;
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drop table dist_t;
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drop table t;
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