Details
Major Description
create table t1 (a int); |
insert into t1 values (1),(2),(3); |
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create table t2 (a int); |
insert into t2 values (10),(11); |
analyze format=json
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select * from (select a from t1 union all select a from t2) TBL; |
Shows something like this:
"table": {
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"table_name": "<derived2>",
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"access_type": "ALL",
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"r_loops": 1,
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"rows": 5,
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"r_rows": 5,
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"r_table_time_ms": 0.039263025,
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"r_other_time_ms": 0.028563309,
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"filtered": 100,
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"r_filtered": 100,
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"materialized": {
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"query_block": {
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"union_result": {
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"table_name": "<union2,3>",
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"access_type": "ALL",
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"r_loops": 0,
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"r_rows": null,
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note r_loops=0, r_rows:null. This is clearly incorrect.
Note that regular UNION (not UNION ALL) one gets correct result:
"materialized": {
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"query_block": {
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"union_result": {
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"table_name": "<union2,3>",
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"access_type": "ALL",
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"r_loops": 1,
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"r_rows": 5,
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