mysql unique Will the order of insertion change?
0
mysql unique Will the order of insertion change?
create table class(
cid int primary key auto_increment,
caption varchar(10)
);
insert class(caption) values
("三年二班"),
("一年三班"),
("三年一班");
create table class1(
cid int primary key auto_increment,
caption char(10) unique
);
insert into class1(caption) values
('三年二班'),
('一年三班'),
('三年一班');
mysql
edited Nov 22 '18 at 2:13
lagom
1
asked Nov 21 '18 at 15:32
cc lcc l
1
add a comment |
0
mysql unique Will the order of insertion change?
create table class(
cid int primary key auto_increment,
caption varchar(10)
);
insert class(caption) values
("三年二班"),
("一年三班"),
("三年一班");
create table class1(
cid int primary key auto_increment,
caption char(10) unique
);
insert into class1(caption) values
('三年二班'),
('一年三班'),
('三年一班');
mysql
edited Nov 22 '18 at 2:13
lagom
1
asked Nov 21 '18 at 15:32
cc lcc l
1
Data is not stored in any specific order you have to use an order by clause to present data in the required order.
– P.Salmon
Nov 21 '18 at 15:36
谢谢thanks i know it
– cc l
Nov 22 '18 at 0:44
Your 2 screenshots show identical data, what your question is about?
– zerkms
Nov 22 '18 at 2:15
Clearly not. You insert the same three rows in the same order in both examples, and they're all assigned the same identicalcidvalues in both examples. You're confusing display order with insertion order. The only thing that affects display order is an ORDER BY. Without one, the database is free to display the data in any order it thinks is most efficient. If you want a specific order, add an ORDER BY. This information is available in any decent SQL book or tutorial. I'd suggest you find one.
– Ken White
Nov 22 '18 at 2:47
Thank you for your answer, I already understand
– cc l
Nov 23 '18 at 6:37
add a comment |
0
0
0
mysql unique Will the order of insertion change?
create table class(
cid int primary key auto_increment,
caption varchar(10)
);
insert class(caption) values
("三年二班"),
("一年三班"),
("三年一班");
create table class1(
cid int primary key auto_increment,
caption char(10) unique
);
insert into class1(caption) values
('三年二班'),
('一年三班'),
('三年一班');
mysql
edited Nov 22 '18 at 2:13
lagom
1
asked Nov 21 '18 at 15:32
cc lcc l
1
mysql unique Will the order of insertion change?
create table class(
cid int primary key auto_increment,
caption varchar(10)
);
insert class(caption) values
("三年二班"),
("一年三班"),
("三年一班");
create table class1(
cid int primary key auto_increment,
caption char(10) unique
);
insert into class1(caption) values
('三年二班'),
('一年三班'),
('三年一班');
mysql
mysql
edited Nov 22 '18 at 2:13
lagom
1
asked Nov 21 '18 at 15:32
cc lcc l
1
edited Nov 22 '18 at 2:13
lagom
1
asked Nov 21 '18 at 15:32
cc lcc l
1
edited Nov 22 '18 at 2:13
lagom
1
edited Nov 22 '18 at 2:13
lagom
1
edited Nov 22 '18 at 2:13
lagom
1
1
asked Nov 21 '18 at 15:32
cc lcc l
1
asked Nov 21 '18 at 15:32
cc lcc l
1
asked Nov 21 '18 at 15:32
cc lcc l
1
1
Data is not stored in any specific order you have to use an order by clause to present data in the required order.
– P.Salmon
Nov 21 '18 at 15:36
谢谢thanks i know it
– cc l
Nov 22 '18 at 0:44
Your 2 screenshots show identical data, what your question is about?
– zerkms
Nov 22 '18 at 2:15
Clearly not. You insert the same three rows in the same order in both examples, and they're all assigned the same identicalcidvalues in both examples. You're confusing display order with insertion order. The only thing that affects display order is an ORDER BY. Without one, the database is free to display the data in any order it thinks is most efficient. If you want a specific order, add an ORDER BY. This information is available in any decent SQL book or tutorial. I'd suggest you find one.
– Ken White
Nov 22 '18 at 2:47
Thank you for your answer, I already understand
– cc l
Nov 23 '18 at 6:37
add a comment |
Data is not stored in any specific order you have to use an order by clause to present data in the required order.
– P.Salmon
Nov 21 '18 at 15:36
谢谢thanks i know it
– cc l
Nov 22 '18 at 0:44
Your 2 screenshots show identical data, what your question is about?
– zerkms
Nov 22 '18 at 2:15
Clearly not. You insert the same three rows in the same order in both examples, and they're all assigned the same identicalcidvalues in both examples. You're confusing display order with insertion order. The only thing that affects display order is an ORDER BY. Without one, the database is free to display the data in any order it thinks is most efficient. If you want a specific order, add an ORDER BY. This information is available in any decent SQL book or tutorial. I'd suggest you find one.
– Ken White
Nov 22 '18 at 2:47
Thank you for your answer, I already understand
– cc l
Nov 23 '18 at 6:37
Data is not stored in any specific order you have to use an order by clause to present data in the required order.
– P.Salmon
Nov 21 '18 at 15:36
Data is not stored in any specific order you have to use an order by clause to present data in the required order.
– P.Salmon
Nov 21 '18 at 15:36
谢谢thanks i know it
– cc l
Nov 22 '18 at 0:44
谢谢thanks i know it
– cc l
Nov 22 '18 at 0:44
Your 2 screenshots show identical data, what your question is about?
– zerkms
Nov 22 '18 at 2:15
Your 2 screenshots show identical data, what your question is about?
– zerkms
Nov 22 '18 at 2:15
Clearly not. You insert the same three rows in the same order in both examples, and they're all assigned the same identical
cid values in both examples. You're confusing display order with insertion order. The only thing that affects display order is an ORDER BY. Without one, the database is free to display the data in any order it thinks is most efficient. If you want a specific order, add an ORDER BY. This information is available in any decent SQL book or tutorial. I'd suggest you find one.– Ken White
Nov 22 '18 at 2:47
Clearly not. You insert the same three rows in the same order in both examples, and they're all assigned the same identical
cid values in both examples. You're confusing display order with insertion order. The only thing that affects display order is an ORDER BY. Without one, the database is free to display the data in any order it thinks is most efficient. If you want a specific order, add an ORDER BY. This information is available in any decent SQL book or tutorial. I'd suggest you find one.– Ken White
Nov 22 '18 at 2:47
Thank you for your answer, I already understand
– cc l
Nov 23 '18 at 6:37
Thank you for your answer, I already understand
– cc l
Nov 23 '18 at 6:37
add a comment |
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Data is not stored in any specific order you have to use an order by clause to present data in the required order.
– P.Salmon
Nov 21 '18 at 15:36
谢谢thanks i know it
– cc l
Nov 22 '18 at 0:44
Your 2 screenshots show identical data, what your question is about?
– zerkms
Nov 22 '18 at 2:15
Clearly not. You insert the same three rows in the same order in both examples, and they're all assigned the same identical
cidvalues in both examples. You're confusing display order with insertion order. The only thing that affects display order is an ORDER BY. Without one, the database is free to display the data in any order it thinks is most efficient. If you want a specific order, add an ORDER BY. This information is available in any decent SQL book or tutorial. I'd suggest you find one.– Ken White
Nov 22 '18 at 2:47
Thank you for your answer, I already understand
– cc l
Nov 23 '18 at 6:37