Using MySQL work bench where the table has an auto generated and auto incremented primary key. Now it increments from the last key by 1:
next-key = last-key +1
I wold like to increment this number by 100:
next-key = last-key + 100
Is there a way to do this in workbench? For the column where the primary key is, there is an option to put in a default expression, if this is where it's done what would the expression look like.
A sample would be helpful.
You can do that at the creation of your table or after by a ALTER TABLE.
ALTER TABLE tbl AUTO_INCREMENT = 100;
Ref. MySQL guide: https://dev.mysql.com/doc/refman/5.7/en/example-auto-increment.html
You can simply set the starting value to 100 as follows
ALTER TABLE table_name AUTO_INCREMENT = 100;
But to increment this number by 100, You need to edit the global variable - auto_increment_increment in your mysql server.
https://dev.mysql.com/doc/refman/5.7/en/replication-options-master.html#sysvar_auto_increment_increment
But this change will effect all the tables in your database server.
Related
I am trying to set up a script to generate a particular set of test data into my database, at the beginning of which I want to clear the tables concerned without dropping constraints (because the test data is not the appropriate place to be rebuilding constraints) and reset the AUTO_INCREMENT for each table since setting up the test data is much, much simpler if I can hard-code many of the IDs.
For example, I have two statements like this (there's a pair for nearly every table):
DELETE FROM AppointmentAttr
ALTER TABLE AppointmentAttr AUTO_INCREMENT = 1
and while the records are deleted, the auto-increment value is not reverting to 1, even though all the documentation and SO answers I can find indicate that this should work.
If I do the same statement in MySQL Workbench it also does not revert it.
This is on an INNODB database.
What am I missing?
(Note: I cannot use TRUNCATE due to the presence of constraints).
MySQL does not permit you to decrease the AUTO_INCREMENT value, as specified here:
http://dev.mysql.com/doc/refman/5.6/en/alter-table.html
You cannot reset the counter to a value less than or equal to the value that is currently in use. For both InnoDB and MyISAM, if the value is less than or equal to the maximum value currently in the AUTO_INCREMENT column, the value is reset to the current maximum AUTO_INCREMENT column value plus one.
Even with your constraints, I would try one of the following:
Explicitly insert your identities for your test data. MySQL doesn't have problems with this, unlike some other database engines
Delete and recreate your identity column (or just change it from being an identity), if the constraints aren't on it itself.
Not use an Identity column and use another method (such as a procedure or outside code) to control your Identity. This is really a last resort and I wouldn't generally recommend it...
Note from OP: It was (1) that was what I needed.
From what I can see about the alter table statement.
You can reset auto increment value by using the ALTER TABLE statement. The syntax of the ALTER TABLE statement to reset auto increment value is as follows:
ALTER TABLE table_name AUTO_INCREMENT = value;
You specify the table name after the ALTER TABLE clause and the value which we want to reset to in the expression AUTO_INCREMENT = value.
Notice that the value must be greater than or equal to the current maximum value of the auto-increment column.
Which is where your problem lies I suspect. So basically you are left with a couple of options as follows:
TRUNCATE TABLE: which according to our discussion is not a option
DROP and RECREATE the table: A long and painful experience
ALTER auto number column: I have not tried this but you could theoretically alter the primary key column from auto number to a int and then make it a auto number again. Something like:
ALTER TABLE tblName MODIFY COLUMN pkKeyColumn BIGINT NOT NULL;
ALTER TABLE tblName MODIFY COLUMN pkKeyColumn BIGINT AUTONUMBER NOT NULL;
Hope these help a little.
Can you not drop the relevant, auto increment column and recreate it? Example follows:
;;assuming your column is called id and your table is tbl
ALTER TABLE tbl DROP COLUMN id;
ALTER TABLE tbl ADD COLUMN id BIGINT UNSIGNED DEFAULT 1 PRIMARY KEY FIRST;
This should work, but I don't use MySQL, just going off the docs. If you need further help, leave a comment and I'll do my best to help out.
I'm sure this has been long answered but when i need to truncate and can't I just do a set foreign_key_checks = 0 then run my truncate and then set foreign_key_checks = 1.
I've run into this problem when I've deleted middle rows from my table.
My answer would be to INSERT NEW DATA TO NOT EXISTING ID.
I expect that my answer still be usefull even if it's PHP not MYSQL.
First fetch your data.
if found not existing row Insert values and exit;
else if not found in whole loop then do insertion for default value;
$rez = mysql_query("SELECT * FROM users");
$exists = 1;
while($row = mysql_fetch_array($rez)){
if ( $exists != $row{'id'} ){
echo "found not existing id: ".$exists;
INSERT INTO users VALUES($exists,.. ,..);
exit;
} $exists += 1;
}
INSERT INTO users VALUES(NULL,.. ,..); ##auto_inc column converts NULL to latest
I HOPE it will help somehow.
In non-problematic circumstances you can do
ALTER TABLE tbl AUTO_INCREMENT = 0;
which brings auto_increment value to the lowest allowed at the time.
ALTER TABLE tbl DROP COLUMN id;
ALTER TABLE tbl ADD id INT NOT NULL AUTO_INCREMENT FIRST, ADD PRIMARY KEY (id); in your phpMyAdmin
ALTER TABLE table_name AUTO_INCREMENT = value;
This worked for me, I had to set it to the last record in my database while going through the operations panel never worked for me.
This worked for me hope it helps.
SET #autoid = 0; UPDATE users set id = #autoid := (#autoid+1); ALTER TABLE users AUTO_INCREMENT = 1;
i have the following problem:
I make an insert to a table. The primaryKey is auto incremented and is an integer.
In one table i have an index of 2345 and suddenly it is updated to 10000.
In another table i have an index of 263564 and it is updated to 1000000.
Does anyone has an idea?
If your inserted value contains field with autoincrement, your key will be updated.
You can change your auto increment value
ALTER TABLE tbl AUTO_INCREMENT = 100;
http://dev.mysql.com/doc/refman/5.6/en/example-auto-increment.html
Also, here is two system variables, which controls behavior of autoincrement.
auto_increment_increment controls the interval between successive column values.
auto_increment_offset determines the starting point for the AUTO_INCREMENT column value
http://dev.mysql.com/doc/refman/5.6/en/replication-options-master.html#sysvar_auto_increment_increment
It was an internal problem. Some Testcases manipulated the Id.
Thanks for your help.
I am wondering how an elegant solution for this issue could look like:
I have a table with approx. 100 entries and one primary key column which has auto increment enabled. The keys start at 200.
Now I would like to disable the auto increment feature and update the key column so that the keys start at "1". Of course, I could just create a second table and just select/insert these values.
But I would like to know whether it is possible to update the key values directly. As the current keys start at 200 and there are less values, it should work somehow, right?
I don't know why do you need to do like this.I think these queries will work
SET #INDEX = 0;
UPDATE `tablename1` SET ID = (#INDEX:=#INDEX+1);
ALTER TABLE `tablename1` AUTO_INCREMENT = 100;
AUTO_INCREMENT is set as 100 to update for next row. you need to set AUTO_INCREMENT with correct value in your query to generate ID that the way you want.
I am facing one problem with one of my project.I have a inventory upload which import data from csv to a innodb table. What happened here is with a multiple load data command (i suppose) the auto increment value get sets to 18446744073709551615 and not letting other insert to work. It was working fine before. I am not sure if the large amount of data in the table creates this issue or not.
Details of the table is as follows
Software version: 5.5.31-0ubuntu0.12.04.1-log - (Ubuntu)
largest insert id used : 17455787099
number of rows in the table : 23887371
some variables realted to this are as follows
auto increment increment 1
auto increment offset 1
autocommit ON
automatic sp privileges ON
innodb autoextend increment 8
innodb autoinc lock mode 1
sql auto is null OFF Documentation
i have removed the delete queries from the table. But still the autoincriment is out of sync
any help is much appreciated
thanks
Nithin
the auto increment value get sets to 18446744073709551615-largest
insert id used : 17455787099
This is a bit confusing.
Try resetting the auto increment value before loading new files:
ALTER TABLE tableName AUTO_INCREMENT = 1
EDIT:
Create a new identical table :
CREATE TABLE tableName LIKE oldtableName;
Copy all rows to the new table, remember to not select the auto_incrementing id.
INSERT INTO tableName (field2, field3, field4)
SELECT field2, field3, field4 FROM oldtableName ORDER BY oldtableName.id;
DROP oldtableName;
RENAME tableName oldtableName;
This will take a while(hours..or more).
EDIT2
If your id column is not referenced by anything
ALTER TABLE tableName DROP id
ALTER TABLE tableName ADD id INT NOT NULL AUTO_INCREMENT FIRST, ADD PRIMARY KEY (id), AUTO_INCREMENT=1
I am trying to set up a script to generate a particular set of test data into my database, at the beginning of which I want to clear the tables concerned without dropping constraints (because the test data is not the appropriate place to be rebuilding constraints) and reset the AUTO_INCREMENT for each table since setting up the test data is much, much simpler if I can hard-code many of the IDs.
For example, I have two statements like this (there's a pair for nearly every table):
DELETE FROM AppointmentAttr
ALTER TABLE AppointmentAttr AUTO_INCREMENT = 1
and while the records are deleted, the auto-increment value is not reverting to 1, even though all the documentation and SO answers I can find indicate that this should work.
If I do the same statement in MySQL Workbench it also does not revert it.
This is on an INNODB database.
What am I missing?
(Note: I cannot use TRUNCATE due to the presence of constraints).
MySQL does not permit you to decrease the AUTO_INCREMENT value, as specified here:
http://dev.mysql.com/doc/refman/5.6/en/alter-table.html
You cannot reset the counter to a value less than or equal to the value that is currently in use. For both InnoDB and MyISAM, if the value is less than or equal to the maximum value currently in the AUTO_INCREMENT column, the value is reset to the current maximum AUTO_INCREMENT column value plus one.
Even with your constraints, I would try one of the following:
Explicitly insert your identities for your test data. MySQL doesn't have problems with this, unlike some other database engines
Delete and recreate your identity column (or just change it from being an identity), if the constraints aren't on it itself.
Not use an Identity column and use another method (such as a procedure or outside code) to control your Identity. This is really a last resort and I wouldn't generally recommend it...
Note from OP: It was (1) that was what I needed.
From what I can see about the alter table statement.
You can reset auto increment value by using the ALTER TABLE statement. The syntax of the ALTER TABLE statement to reset auto increment value is as follows:
ALTER TABLE table_name AUTO_INCREMENT = value;
You specify the table name after the ALTER TABLE clause and the value which we want to reset to in the expression AUTO_INCREMENT = value.
Notice that the value must be greater than or equal to the current maximum value of the auto-increment column.
Which is where your problem lies I suspect. So basically you are left with a couple of options as follows:
TRUNCATE TABLE: which according to our discussion is not a option
DROP and RECREATE the table: A long and painful experience
ALTER auto number column: I have not tried this but you could theoretically alter the primary key column from auto number to a int and then make it a auto number again. Something like:
ALTER TABLE tblName MODIFY COLUMN pkKeyColumn BIGINT NOT NULL;
ALTER TABLE tblName MODIFY COLUMN pkKeyColumn BIGINT AUTONUMBER NOT NULL;
Hope these help a little.
Can you not drop the relevant, auto increment column and recreate it? Example follows:
;;assuming your column is called id and your table is tbl
ALTER TABLE tbl DROP COLUMN id;
ALTER TABLE tbl ADD COLUMN id BIGINT UNSIGNED DEFAULT 1 PRIMARY KEY FIRST;
This should work, but I don't use MySQL, just going off the docs. If you need further help, leave a comment and I'll do my best to help out.
I'm sure this has been long answered but when i need to truncate and can't I just do a set foreign_key_checks = 0 then run my truncate and then set foreign_key_checks = 1.
I've run into this problem when I've deleted middle rows from my table.
My answer would be to INSERT NEW DATA TO NOT EXISTING ID.
I expect that my answer still be usefull even if it's PHP not MYSQL.
First fetch your data.
if found not existing row Insert values and exit;
else if not found in whole loop then do insertion for default value;
$rez = mysql_query("SELECT * FROM users");
$exists = 1;
while($row = mysql_fetch_array($rez)){
if ( $exists != $row{'id'} ){
echo "found not existing id: ".$exists;
INSERT INTO users VALUES($exists,.. ,..);
exit;
} $exists += 1;
}
INSERT INTO users VALUES(NULL,.. ,..); ##auto_inc column converts NULL to latest
I HOPE it will help somehow.
In non-problematic circumstances you can do
ALTER TABLE tbl AUTO_INCREMENT = 0;
which brings auto_increment value to the lowest allowed at the time.
ALTER TABLE tbl DROP COLUMN id;
ALTER TABLE tbl ADD id INT NOT NULL AUTO_INCREMENT FIRST, ADD PRIMARY KEY (id); in your phpMyAdmin
ALTER TABLE table_name AUTO_INCREMENT = value;
This worked for me, I had to set it to the last record in my database while going through the operations panel never worked for me.
This worked for me hope it helps.
SET #autoid = 0; UPDATE users set id = #autoid := (#autoid+1); ALTER TABLE users AUTO_INCREMENT = 1;