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drop table if exists t1,t2;
select 1, 1.0, -1, "hello", NULL;
Catalog Database Table Table_alias Column Column_alias Name Type Length Max length Is_null Flags Decimals Charsetnr
def 1 8 1 1 N 32769 0 8
def 1.0 5 3 3 N 32769 1 8
def -1 8 1 2 N 32769 0 8
def hello 254 5 5 N 1 31 8
def NULL 6 0 0 Y 32768 0 8
1 1.0 -1 hello NULL
1 1.0 -1 hello NULL
create table t1 (a tinyint, b smallint, c mediumint, d int, e bigint, f float(3,2), g double(4,3), h decimal(5,4), i year, j date, k timestamp, l datetime, m enum('a','b'), n set('a','b'), o char(10));
select * from t1;
Catalog Database Table Table_alias Column Column_alias Name Type Length Max length Is_null Flags Decimals Charsetnr
def test t1 t1 a a 1 4 0 Y 32768 0 63
def test t1 t1 b b 2 6 0 Y 32768 0 63
def test t1 t1 c c 9 9 0 Y 32768 0 63
def test t1 t1 d d 3 11 0 Y 32768 0 63
def test t1 t1 e e 8 20 0 Y 32768 0 63
def test t1 t1 f f 4 3 0 Y 32768 2 63
def test t1 t1 g g 5 4 0 Y 32768 3 63
def test t1 t1 h h 0 7 0 Y 32768 4 63
def test t1 t1 i i 13 4 0 Y 32864 0 63
def test t1 t1 j j 10 10 0 Y 128 0 63
def test t1 t1 k k 7 19 0 N 1217 0 63
def test t1 t1 l l 12 19 0 Y 128 0 63
def test t1 t1 m m 254 1 0 Y 256 0 8
def test t1 t1 n n 254 3 0 Y 2048 0 8
def test t1 t1 o o 254 10 0 Y 0 0 8
a b c d e f g h i j k l m n o
select a b, b c from t1 as t2;
Catalog Database Table Table_alias Column Column_alias Name Type Length Max length Is_null Flags Decimals Charsetnr
def test t1 t2 a b 1 4 0 Y 32768 0 63
def test t1 t2 b c 2 6 0 Y 32768 0 63
b c
drop table t1;
CREATE TABLE t1 (id tinyint(3) default NULL, data varchar(255) default NULL);
INSERT INTO t1 VALUES (1,'male'),(2,'female');
CREATE TABLE t2 (id tinyint(3) unsigned default NULL, data char(3) default '0');
INSERT INTO t2 VALUES (1,'yes'),(2,'no');
select t1.id, t1.data, t2.data from t1, t2 where t1.id = t2.id;
Catalog Database Table Table_alias Column Column_alias Name Type Length Max length Is_null Flags Decimals Charsetnr
def test t1 t1 id id 1 3 1 Y 32768 0 63
def test t1 t1 data data 253 255 6 Y 0 0 8
def test t2 t2 data data 254 3 3 Y 0 0 8
id data data
1 male yes
2 female no
select t1.id, t1.data, t2.data from t1, t2 where t1.id = t2.id order by t1.id;
Catalog Database Table Table_alias Column Column_alias Name Type Length Max length Is_null Flags Decimals Charsetnr
def test t1 t1 id id 1 3 1 Y 32768 0 63
def test t1 t1 data data 253 255 6 Y 0 0 8
def test t2 t2 data data 254 3 3 Y 0 0 8
id data data
1 male yes
2 female no
select t1.id from t1 union select t2.id from t2;
Catalog Database Table Table_alias Column Column_alias Name Type Length Max length Is_null Flags Decimals Charsetnr
def test t1 t1 id id 1 3 1 Y 32768 0 63
id
1
2
drop table t1,t2;
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