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68ed3a81f2
Count the "gap" time between table accesses and display it as r_other_time_ms in the "table" element. * The advantage of this approach is that it doesn't add any new my_timer_cycles() calls. * The disadvantage is that the definition of what is done during "other time" is not that clear: it includes checking the WHERE (for this table), constructing index lookup tuple (for the next table) writing to GROUP BY temporary table (as we dont account for that time separately [yet], etc)
87 lines
2 KiB
Text
87 lines
2 KiB
Text
create table t2(a int);
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insert into t2 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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create table t1 (
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a int not null
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) partition by key(a);
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insert into t1 select a from t2;
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explain partitions select * from t1 where a in (2,3,4);
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id select_type table partitions type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 p0 ALL NULL NULL NULL NULL 10 Using where
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explain format=json select * from t1 where a in (2,3,4);
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EXPLAIN
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{
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"query_block": {
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"select_id": 1,
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"table": {
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"table_name": "t1",
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"partitions": ["p0"],
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"access_type": "ALL",
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"rows": 10,
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"filtered": 100,
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"attached_condition": "t1.a in (2,3,4)"
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}
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}
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}
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analyze format=json select * from t1 where a in (2,3,4);
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ANALYZE
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{
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"query_block": {
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"select_id": 1,
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"r_loops": 1,
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"r_total_time_ms": "REPLACED",
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"table": {
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"table_name": "t1",
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"partitions": ["p0"],
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"access_type": "ALL",
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"r_loops": 1,
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"rows": 10,
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"r_rows": 10,
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"r_table_time_ms": "REPLACED",
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"r_other_time_ms": "REPLACED",
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"filtered": 100,
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"r_filtered": 30,
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"attached_condition": "t1.a in (2,3,4)"
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}
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}
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}
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analyze format=json update t1 set a=a+10 where a in (2,3,4);
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ANALYZE
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{
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"query_block": {
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"select_id": 1,
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"r_total_time_ms": "REPLACED",
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"buffer": {
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"table": {
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"update": 1,
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"table_name": "t1",
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"partitions": ["p0"],
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"access_type": "ALL",
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"rows": 10,
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"r_rows": 10,
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"r_filtered": 30,
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"r_total_time_ms": "REPLACED",
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"attached_condition": "t1.a in (2,3,4)"
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}
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}
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}
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}
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analyze format=json delete from t1 where a in (20,30,40);
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ANALYZE
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{
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"query_block": {
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"select_id": 1,
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"r_total_time_ms": "REPLACED",
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"table": {
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"delete": 1,
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"table_name": "t1",
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"partitions": ["p0"],
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"access_type": "ALL",
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"rows": 10,
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"r_rows": 10,
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"r_filtered": 0,
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"r_total_time_ms": "REPLACED",
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"attached_condition": "t1.a in (20,30,40)"
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}
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}
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}
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drop table t1,t2;
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