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-rw-r--r--mysql-test/main/join_cache_cardinality.result105
1 files changed, 105 insertions, 0 deletions
diff --git a/mysql-test/main/join_cache_cardinality.result b/mysql-test/main/join_cache_cardinality.result
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+create table t1 (a int, b int, c int);
+insert into t1 select seq,seq/2, seq/4 from seq_1_to_100;
+create table t2 (a int, b int, c int);
+insert into t2 select seq, seq/2, seq/4 from seq_1_to_200;
+analyze table t1,t2 persistent for all;
+Table Op Msg_type Msg_text
+test.t1 analyze status Engine-independent statistics collected
+test.t1 analyze status OK
+test.t2 analyze status Engine-independent statistics collected
+test.t2 analyze status OK
+set optimizer_trace=1;
+set join_cache_level=6;
+set optimizer_switch='hash_join_cardinality=on';
+explain select *
+from t1, t2
+where t1.a=t2.a and t1.a=t2.b and t1.c=t2.c;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 100 Using where
+1 SIMPLE t2 hash_ALL NULL #hash#$hj 15 test.t1.a,test.t1.a,test.t1.c 200 Using where; Using join buffer (flat, BNLH join)
+set @json= (select trace from information_schema.optimizer_trace);
+select json_detailed(json_extract(@json, '$**.hash_join_cardinality')) as JS;
+JS
+[
+ {
+ "hash_join_columns":
+ [
+ {
+ "field": "a",
+ "avg_frequency": 1
+ },
+ {
+ "field": "b",
+ "avg_frequency": 2
+ },
+ {
+ "field": "c",
+ "avg_frequency": 3.9216
+ }
+ ],
+ "rows": 1
+ }
+]
+select json_detailed(json_extract(@json, '$**.rest_of_plan[*].rows_for_plan'))
+as ROWS_FOR_PLAN;
+ROWS_FOR_PLAN
+[100]
+explain select *
+from t1, t2 where t1.c=t2.c;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 100 Using where
+1 SIMPLE t2 hash_ALL NULL #hash#$hj 5 test.t1.c 200 Using where; Using join buffer (flat, BNLH join)
+set @json= (select trace from information_schema.optimizer_trace);
+select json_detailed(json_extract(@json, '$**.hash_join_cardinality')) as JS;
+JS
+[
+ {
+ "hash_join_columns":
+ [
+ {
+ "field": "c",
+ "avg_frequency": 3.9216
+ }
+ ],
+ "rows": 3.9216
+ }
+]
+select json_detailed(json_extract(@json, '$**.rest_of_plan[*].rows_for_plan'))
+as ROWS_FOR_PLAN;
+ROWS_FOR_PLAN
+[392.16]
+explain select *
+from t1 straight_join t2 where t1.c=t2.c and t2.a<30;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 100 Using where
+1 SIMPLE t2 hash_ALL NULL #hash#$hj 5 test.t1.c 200 Using where; Using join buffer (flat, BNLH join)
+set @json= (select trace from information_schema.optimizer_trace);
+# Note that rows is the same:
+select json_detailed(json_extract(@json, '$**.hash_join_cardinality')) as JS;
+JS
+[
+ {
+ "hash_join_columns":
+ [
+ {
+ "field": "c",
+ "avg_frequency": 3.9216
+ }
+ ],
+ "rows": 3.9216
+ }
+]
+# Despite available selectivity:
+select json_detailed(json_extract(@json, '$**.selectivity_for_columns')) as JS;
+JS
+[
+ [
+ {
+ "column_name": "a",
+ "ranges":
+ ["NULL < a < 30"],
+ "selectivity_from_histogram": 0.145
+ }
+ ]
+]
+drop table t1,t2;