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|
FLUSH STATUS;
create table t1(abc int primary key, xyz int invisible);
SHOW STATUS LIKE 'Feature_invisible_columns';
Variable_name Value
Feature_invisible_columns 1
desc t1;
Field Type Null Key Default Extra
abc int(11) NO PRI NULL
xyz int(11) YES NULL INVISIBLE
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`abc` int(11) NOT NULL,
`xyz` int(11) INVISIBLE DEFAULT NULL,
PRIMARY KEY (`abc`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1
select TABLE_CATALOG,TABLE_SCHEMA,TABLE_NAME,COLUMN_NAME,EXTRA from INFORMATION_SCHEMA.COLUMNS where TABLE_SCHEMA='test' and TABLE_NAME='t1';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME EXTRA
def test t1 abc
def test t1 xyz INVISIBLE
drop table t1;
create table t1(a1 int invisible);
ERROR 42000: A table must have at least 1 column
create table t1(a1 blob,invisible(a1));
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '(a1))' at line 1
create table t1(a1 int primary key invisible ,a2 int unique invisible , a3 blob,a4 int not null invisible unique);
ERROR HY000: Invisible column `a1` must have a default value
create table t1(abc int not null invisible);
ERROR 42000: A table must have at least 1 column
MDEV-14849 CREATE + ALTER with user-invisible columns produce invalid table definition
create or replace table t1 (pk int auto_increment primary key invisible, i int);
alter table t1 modify pk int invisible;
ERROR HY000: Invisible column `pk` must have a default value
drop table t1;
create table t1(a int invisible, b int);
insert into t1 values(1);
insert into t1(a) values(2);
insert into t1(b) values(3);
insert into t1(a,b) values(5,5);
select * from t1;
b
1
NULL
3
5
select a,b from t1;
a b
NULL 1
2 NULL
NULL 3
5 5
delete from t1;
insert into t1 values(1),(2),(3),(4);
select * from t1;
b
1
2
3
4
select a from t1;
a
NULL
NULL
NULL
NULL
drop table t1;
#more complex case of invisible
create table t1(a int , b int invisible , c int invisible auto_increment unique, d blob , e int unique, f int);
desc t1;
Field Type Null Key Default Extra
a int(11) YES NULL
b int(11) YES NULL INVISIBLE
c int(11) NO PRI NULL auto_increment, INVISIBLE
d blob YES NULL
e int(11) YES UNI NULL
f int(11) YES NULL
insert into t1 values(1,'d blob',1,1),(1,'d blob',11,1),(1,'d blob',2,1),(1,'d blob',3,1),(1,'d blob',41,1);
select * from t1;
a d e f
1 d blob 1 1
1 d blob 11 1
1 d blob 2 1
1 d blob 3 1
1 d blob 41 1
select a,b,c,d,e,f from t1;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
drop table t1;
#more complex case of invisible with sql_mode=NO_AUTO_VALUE_ON_ZERO
set sql_mode='NO_AUTO_VALUE_ON_ZERO';
create table t1(a int , b int invisible , c int invisible auto_increment unique, d blob , e int unique, f int);
desc t1;
Field Type Null Key Default Extra
a int(11) YES NULL
b int(11) YES NULL INVISIBLE
c int(11) NO PRI NULL auto_increment, INVISIBLE
d blob YES NULL
e int(11) YES UNI NULL
f int(11) YES NULL
insert into t1 values(1,'d blob',1,1),(1,'d blob',11,1),(1,'d blob',2,1),(1,'d blob',3,1),(1,'d blob',41,1);
select * from t1;
a d e f
1 d blob 1 1
1 d blob 11 1
1 d blob 2 1
1 d blob 3 1
1 d blob 41 1
select a,b,c,d,e,f from t1;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
drop table t1;
set sql_mode='';
create table sdsdsd(a int , b int, invisible(a,b));
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '(a,b))' at line 1
create table t1(a int,abc int as (a mod 3) virtual invisible);
desc t1;
Field Type Null Key Default Extra
a int(11) YES NULL
abc int(11) YES NULL VIRTUAL GENERATED, INVISIBLE
insert into t1 values(1,default);
ERROR 21S01: Column count doesn't match value count at row 1
insert into t1 values(1),(22),(233);
select * from t1;
a
1
22
233
select a,abc from t1;
a abc
1 1
22 1
233 2
drop table t1;
create table t1(abc int primary key invisible auto_increment, a int);
desc t1;
Field Type Null Key Default Extra
abc int(11) NO PRI NULL auto_increment, INVISIBLE
a int(11) YES NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`abc` int(11) NOT NULL INVISIBLE AUTO_INCREMENT,
`a` int(11) DEFAULT NULL,
PRIMARY KEY (`abc`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 values(1);
insert into t1 values(2);
insert into t1 values(3);
select * from t1;
a
1
2
3
select abc,a from t1;
abc a
1 1
2 2
3 3
delete from t1;
insert into t1 values(1),(2),(3),(4),(6);
select abc,a from t1;
abc a
4 1
5 2
6 3
7 4
8 6
drop table t1;
create table t1(abc int);
alter table t1 change abc ss int invisible;
ERROR 42000: A table must have at least 1 column
alter table t1 add column xyz int;
alter table t1 modify column abc int ;
desc t1;
Field Type Null Key Default Extra
abc int(11) YES NULL
xyz int(11) YES NULL
insert into t1 values(22);
ERROR 21S01: Column count doesn't match value count at row 1
alter table t1 modify column abc int invisible;
desc t1;
Field Type Null Key Default Extra
abc int(11) YES NULL INVISIBLE
xyz int(11) YES NULL
insert into t1 values(12);
drop table t1;
#some test on copy table structure with table data;
#table with invisible fields and unique keys;
create table t1(a int , b int invisible , c int invisible auto_increment unique, d blob , e int unique, f int);
desc t1;
Field Type Null Key Default Extra
a int(11) YES NULL
b int(11) YES NULL INVISIBLE
c int(11) NO PRI NULL auto_increment, INVISIBLE
d blob YES NULL
e int(11) YES UNI NULL
f int(11) YES NULL
insert into t1 values(1,'d blob',1,1),(1,'d blob',11,1),(1,'d blob',2,1),(1,'d blob',3,1),(1,'d blob',41,1);
select * from t1;
a d e f
1 d blob 1 1
1 d blob 11 1
1 d blob 2 1
1 d blob 3 1
1 d blob 41 1
select a,b,c,d,e,f from t1;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
#this won't copy invisible fields and keys;
create table t2 as select * from t1;
desc t2;
Field Type Null Key Default Extra
a int(11) YES NULL
d blob YES NULL
e int(11) YES NULL
f int(11) YES NULL
select * from t2;
a d e f
1 d blob 1 1
1 d blob 11 1
1 d blob 2 1
1 d blob 3 1
1 d blob 41 1
select a,b,c,d,e,f from t2;
ERROR 42S22: Unknown column 'b' in 'field list'
drop table t2;
#now this will copy invisible fields
create table t2 as select a,b,c,d,e,f from t1;
desc t2;
Field Type Null Key Default Extra
a int(11) YES NULL
b int(11) YES NULL
c int(11) NO 0
d blob YES NULL
e int(11) YES NULL
f int(11) YES NULL
select * from t2;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
select a,b,c,d,e,f from t2;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
drop table t2,t1;
#some test related to copy of data from one table to another;
create table t1(a int , b int invisible , c int invisible auto_increment unique, d blob , e int unique, f int);
insert into t1 values(1,'d blob',1,1),(1,'d blob',11,1),(1,'d blob',2,1),(1,'d blob',3,1),(1,'d blob',41,1);
select a,b,c,d,e,f from t1;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
create table t2(a int , b int invisible , c int invisible , d blob , e int unique, f int);
insert into t2 select * from t1;
select a,b,c,d,e,f from t2;
a b c d e f
1 NULL NULL d blob 1 1
1 NULL NULL d blob 11 1
1 NULL NULL d blob 2 1
1 NULL NULL d blob 3 1
1 NULL NULL d blob 41 1
truncate t2;
insert into t2 (a,b,c,d,e,f) select a,b,c,d,e,f from t1;
select a,b,c,d,e,f from t2;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
truncate t2;
drop table t1,t2;
#some test related to creating view on table with invisible column;
create table t1(a int , b int invisible , c int invisible auto_increment unique, d blob , e int unique, f int);
insert into t1 values(1,'d blob',1,1),(1,'d blob',11,1),(1,'d blob',2,1),(1,'d blob',3,1),(1,'d blob',41,1);
create view v as select * from t1;
desc v;
Field Type Null Key Default Extra
a int(11) YES NULL
d blob YES NULL
e int(11) YES NULL
f int(11) YES NULL
select * from v;
a d e f
1 d blob 1 1
1 d blob 11 1
1 d blob 2 1
1 d blob 3 1
1 d blob 41 1
#v does not have invisible column;
select a,b,c,d,e,f from v;
ERROR 42S22: Unknown column 'b' in 'field list'
insert into v values(1,21,32,4);
select * from v;
a d e f
1 d blob 1 1
1 d blob 11 1
1 d blob 2 1
1 d blob 3 1
1 d blob 41 1
1 21 32 4
insert into v(a,b,c,d,e,f) values(1,12,3,4,5,6);
ERROR 42S22: Unknown column 'b' in 'field list'
drop view v;
create view v as select a,b,c,d,e,f from t1;
desc v;
Field Type Null Key Default Extra
a int(11) YES NULL
b int(11) YES NULL
c int(11) NO 0
d blob YES NULL
e int(11) YES NULL
f int(11) YES NULL
select * from v;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
1 NULL 6 21 32 4
#v does have invisible column but they aren't invisible anymore.
select a,b,c,d,e,f from v;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
1 NULL 6 21 32 4
insert into v values(1,26,33,4,45,66);
select a,b,c,d,e,f from v;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
1 NULL 6 21 32 4
1 26 33 4 45 66
insert into v(a,b,c,d,e,f) values(1,32,31,41,5,6);
select a,b,c,d,e,f from v;
a b c d e f
1 NULL 1 d blob 1 1
1 NULL 2 d blob 11 1
1 NULL 3 d blob 2 1
1 NULL 4 d blob 3 1
1 NULL 5 d blob 41 1
1 NULL 6 21 32 4
1 26 33 4 45 66
1 32 31 41 5 6
drop view v;
drop table t1;
#now invisible column in where and some join query
create table t1 (a int unique , b int invisible unique, c int unique invisible);
insert into t1(a,b,c) values(1,1,1);
insert into t1(a,b,c) values(2,2,2);
insert into t1(a,b,c) values(3,3,3);
insert into t1(a,b,c) values(4,4,4);
insert into t1(a,b,c) values(21,21,26);
insert into t1(a,b,c) values(31,31,35);
insert into t1(a,b,c) values(41,41,45);
insert into t1(a,b,c) values(22,22,24);
insert into t1(a,b,c) values(32,32,33);
insert into t1(a,b,c) values(42,42,43);
explain select * from t1 where b=3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const b b 5 const 1
select * from t1 where b=3;
a
3
explain select * from t1 where c=3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const c c 5 const 1
select * from t1 where c=3;
a
3
create table t2 as select a,b,c from t1;
desc t2;
Field Type Null Key Default Extra
a int(11) YES NULL
b int(11) YES NULL
c int(11) YES NULL
explain select * from t1,t2 where t1.b = t2.c and t1.c = t2.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 10 Using where
1 SIMPLE t1 ref b,c b 5 test.t2.c 1 Using where
select * from t1,t2 where t1.b = t2.c and t1.c = t2.b;
a a b c
1 1 1 1
2 2 2 2
3 3 3 3
4 4 4 4
drop table t1,t2;
#Unhide invisible columns
create table t1 (a int primary key, b int invisible, c int invisible unique);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) NOT NULL,
`b` int(11) INVISIBLE DEFAULT NULL,
`c` int(11) INVISIBLE DEFAULT NULL,
PRIMARY KEY (`a`),
UNIQUE KEY `c` (`c`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1
desc t1;
Field Type Null Key Default Extra
a int(11) NO PRI NULL
b int(11) YES NULL INVISIBLE
c int(11) YES UNI NULL INVISIBLE
alter table t1 modify column b int;
desc t1;
Field Type Null Key Default Extra
a int(11) NO PRI NULL
b int(11) YES NULL
c int(11) YES UNI NULL INVISIBLE
alter table t1 change column c d int;
desc t1;
Field Type Null Key Default Extra
a int(11) NO PRI NULL
b int(11) YES NULL
d int(11) YES UNI NULL
drop table t1;
SHOW STATUS LIKE 'Feature_invisible_columns';
Variable_name Value
Feature_invisible_columns 52
#invisible is non reserved
create table t1(a int unique , invisible int invisible, c int );
desc t1;
Field Type Null Key Default Extra
a int(11) YES UNI NULL
invisible int(11) YES NULL INVISIBLE
c int(11) YES NULL
alter table t1 change column invisible hid int invisible;
desc t1;
Field Type Null Key Default Extra
a int(11) YES UNI NULL
hid int(11) YES NULL INVISIBLE
c int(11) YES NULL
drop table t1;
CREATE TABLE t1 (b int);
INSERT t1 values(1);
INSERT t1 values(2);
INSERT t1 values(3);
INSERT t1 values(4);
INSERT t1 values(5);
CREATE TABLE t2 (a int invisible) SELECT * FROM t1;
select * from t2 order by b;
b
1
2
3
4
5
select a,b from t2 order by b;
a b
NULL 1
NULL 2
NULL 3
NULL 4
NULL 5
CREATE TABLE t3 (b int, a int invisible) SELECT * FROM t1;
select * from t3 order by b;
b
1
2
3
4
5
select a,b from t3 order by b;
a b
NULL 1
NULL 2
NULL 3
NULL 4
NULL 5
CREATE TABLE t4 (b int invisible) SELECT * FROM t1;
ERROR 42000: A table must have at least 1 column
CREATE TABLE t5 (a int invisible) SELECT b as a FROM t1;
ERROR 42000: A table must have at least 1 column
drop table t1,t2,t3;
create table t1 (a int , b int invisible default 3, c int , d int invisible default 6);
CREATE PROCEDURE
insert_t1(a int, b int)
MODIFIES SQL DATA
insert into t1 values(a,b);
//
call insert_t1(1,1);
call insert_t1(2,2);
select * from t1 order by a;
a c
1 1
2 2
select a,b,c,d from t1 order by a;
a b c d
1 3 1 6
2 3 2 6
DROP PROCEDURE insert_t1;
delete from t1;
prepare insert_1 from "insert into t1 values(@a,@c)";
prepare insert_2 from "insert into t1(a,b,c) values(@a,@b,@c)";
set @a=1, @c=1;
execute insert_1;
set @a=2,@b=2, @c=2;
execute insert_2;
select a,b,c,d from t1 order by a;
a b c d
1 3 1 6
2 2 2 6
drop table t1;
create table t1(a int default 5 invisible, b int);
create table t2(a int default (b+11) invisible, b int);
insert into t1 values(1);
select a,b from t1;
a b
5 1
insert into t2 values(1);
select a,b from t2;
a b
NULL 1
drop table t1,t2;
create table t1 (a int invisible, b int, c int);
create table t2 (a int, b int, d int);
insert t1 (a,b,c) values (0,2,3), (10, 20, 30);
insert t2 (a,b,d) values (1,2,4), (10, 30, 40);
select * from t1 join t2 using (a);
b c b d
20 30 30 40
select * from t1 natural join t2;
b c a d
2 3 1 4
drop table t1, t2;
CREATE TABLE t1 (c CHAR(3), t TIMESTAMP invisible);
INSERT INTO t1 (c,t) VALUES ('foo','2000-01-01 00:00:00');
CREATE TRIGGER tr BEFORE INSERT ON t1 FOR EACH ROW SET @a= 1;
INSERT INTO t1 SELECT * FROM t1;
DROP TABLE t1;
create or replace table t1 (a int, b int invisible);
insert into t1 values (1),(2);
select * from t1 into outfile 'f';
Warnings:
Warning 1287 '<select expression> INTO <destination>;' is deprecated and will be removed in a future release. Please use 'SELECT <select list> INTO <destination> FROM...' instead
load data infile 'f' into table t1;
select a,b from t1;
a b
1 NULL
2 NULL
1 NULL
2 NULL
load data infile 'f' into table t1 (a,@v) SET b=@v;
select a,b from t1;
a b
1 NULL
2 NULL
1 NULL
2 NULL
1 NULL
2 NULL
load data infile 'f' into table t1 (a,@v) SET b=a;
select a,b from t1;
a b
1 NULL
2 NULL
1 NULL
2 NULL
1 NULL
2 NULL
1 1
2 2
truncate table t1;
insert into t1(a,b) values (1,1),(2,2);
select a,b from t1 into outfile 'a';
Warnings:
Warning 1287 '<select expression> INTO <destination>;' is deprecated and will be removed in a future release. Please use 'SELECT <select list> INTO <destination> FROM...' instead
load data infile 'a' into table t1(a,b);
select a,b from t1;
a b
1 1
2 2
1 1
2 2
load data infile 'a' into table t1 (a,@v) SET b=@v;
select a,b from t1;
a b
1 1
2 2
1 1
2 2
1 1
2 2
load data infile 'a' into table t1 (a,@v) SET b=@v+2;
select a,b from t1;
a b
1 1
2 2
1 1
2 2
1 1
2 2
1 3
2 4
drop table t1;
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