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drop table if exists t1,t2;
create table t1 (i int, j int);
insert into t1 values (1,2), (3,4), (5,6), (7,8);
select count(*) from t1 procedure analyse();
Field_name Min_value Max_value Min_length Max_length Empties_or_zeros Nulls Avg_value_or_avg_length Std Optimal_fieldtype
-6510615555426900571 -6510615555426900571 -6510615555426900571 -6510615555426900571
select * from t1 procedure analyse();
Field_name Min_value Max_value Min_length Max_length Empties_or_zeros Nulls Avg_value_or_avg_length Std Optimal_fieldtype
t1.i 1 7 1 1 0 0 4.0000 2.2361 ENUM('1','3','5','7') NOT NULL
t1.j 2 8 1 1 0 0 5.0000 2.2361 ENUM('2','4','6','8') NOT NULL
create table t2 select * from t1 procedure analyse();
select * from t2;
Field_name Min_value Max_value Min_length Max_length Empties_or_zeros Nulls Avg_value_or_avg_length Std Optimal_fieldtype
t1.i 1 7 1 1 0 0 4.0000 2.2361 ENUM('1','3','5','7') NOT NULL
t1.j 2 8 1 1 0 0 5.0000 2.2361 ENUM('2','4','6','8') NOT NULL
drop table t1,t2;
EXPLAIN SELECT 1 FROM (SELECT 1) a PROCEDURE ANALYSE();
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> system NULL NULL NULL NULL 1
2 DERIVED NULL NULL NULL NULL NULL NULL NULL No tables used
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