Alter column for primary key not working - sql

I created a new table, without auto increment of the primary key and inserted set of predefined data's into the table. Now I need to set the auto increment for the primary key, which I'm not able to set. please suggest the mistake i have done in the query below.
ALTER TABLE SYNCBASE.AUTO_LOAD_DATASOURCES
ALTER COLUMN ID BIGINT NOT NULL PRIMARY KEY GENERATED ALWAYS AS IDENTITY (START WITH 62, INCREMENT BY 1)
Till 61 rows i have inserted the records, it has to increment from 62 onwards. but i;m getting error as
Error: DB2 SQL Error: SQLCODE=-104, SQLSTATE=42601, SQLERRMC=BIGINT;RCES
ALTER COLUMN ID;SET, DRIVER=3.53.95
SQLState: 42601
ErrorCode: -104
Thanks in advance

The issue might be coming from the fact that you already have data in your database and modifying the primary key would violate the data integrity. Or you may check whether your DBMS allows you to make changes to a table after creating it.

first of all... we need to drop the identity and then alter the column, only then it works.
alter table SYNCBASE.AUTO_LOAD_DATASOURCES alter column ID drop identity;
alter table SYNCBASE.AUTO_LOAD_DATASOURCES alter column ID set generated always as identity (start with 62, INCREMENT BY 1);

There is a syntax error in the DDL statement. The column definition doesn't need to be repeated. This statement will work:
ALTER TABLE SYNCBASE.AUTO_LOAD_DATASOURCES
ALTER COLUMN ID SET GENERATED ALWAYS AS IDENTITY (START WITH 62);

Related

Set IDENTITY to existing column

I have a table which is having a column name ID field of integer type. It was declared IDENTITY. And it has data according to IDENTITY. But recently I removed IDENTITY column from that table. Now I want to change that to IDENTITY again. But this query says incorrect syntax
Alter table FuleConsumptions alter column TransactionID INT IDENTITY(1,1);
But I can perform the same task using SQL server designer in properties of the table.
What am I doing wrong here?
I think The identity column will hold the sequence of number thats why it thrown error
better you drop column then create it again and set IDENTITY
Alter Table FuleConsumptions Drop Column TransactionID
Go
ALTER TABLE FuleConsumptions
ADD TransactionID int;
go
Alter table FuleConsumptions alter column TransactionID INT IDENTITY(1,1);

SQL Alter Statement for Primary Key Column

I am having a problem making the column I am adding NOT NULL using the SQL ALTER statement. I am fairly novice with SQL so any guidance would be great. I am using SQL Sever 2008 and I am receiving an error stating that the column cannot be added to the table because it does not allow nulls and does not specify a default definition. I already have data in the table and I am just looking to add an incremental primary key.
This is the SQL I am using to generate the column
ALTER TABLE EPUpdates.GenInfo_OpType3
ADD KeyOpType Integer NOT NULL
This is the SQL I am using to make it a Primary Key/ Identity Column
ALTER TABLE EPUpdates.GenInfo_OpType3
ADD PRIMARY KEY(KeyOpType)
try to add a default value to your column, but if you want to make it as a primary key, the values must be different for each row, so you have to update these value after creating the new column and before create your primary index.
ALTER TABLE EPUpdates.GenInfo_OpType3
ADD KeyOpType Integer NOT NULL Default 0
If your trying to to add an incremental primary key then try this
ALTER TABLE EPUpdates.GenInfo_OpType3
ADD KeyOpType INT NOT NULL IDENTITY (1,1) PRIMARY KEY

How to add a PK to an existing table in DB2?

I am facing one problem. I have a table already create in DB2.
CREATE TABLE "DDL12"
(
"D4_1" decimal(10,0),
"D4_2" decimal(10,0),
);
I am trying to create a PK on this table as :-
ALTER TABLE "DDL12" ADD CONSTRAINT "Key4" PRIMARY KEY ("D4_1");
But while running the command, I am getting the error saying D4_1 is NULLABLE.
Now, how can I create a PK on this table?
Thanks
Yes, this is due the fact, that your database "could have" rows having NULL value in that non PK column right now.
So first set the column to NOT NULL (+ make sure having a unique value in all rows) and then set the primary key with the command above.
You can change a column to not NULL like this:
ALTER TABLE "DDL12"
MODIFY "D4_1" decimal(10,0) NOT NULL;

How to add unique column in sybase?

I have a sybase db table in which i need to add a new column.
The conditions: The column must not allow nulls and be unique.
what is the alter table sql to achieve this?
EDIT:
It is a varchar type column.Yes the table as of now is empty, but when filled it is ensured that unique values would be filled in.
I tired executing
alter table Test add Name varchar not null unique
i get error saying default value must be specified as not null is given.
but i want to add unique constraint so do i really need to specify default?
thanks
Unique values are specified as part of an index on the column, not in the column definition itself.
Try:
alter table Test add Name varchar not null
create unique index index_name_unique on Test (Name)
The ASE reference manual can help with more detail.
Once a table has been created Sybase ASE does not allow addition of NOT NULL column directly unless a default is specified for the column. However, if the table is still empty you can do the following -
First add the new column as a NULL column to the table using alter table command -
alter table Test add Name varchar(100) null
Once this has been done, try modifying the same column Name in the table Test using the alter table script -
alter table Test modify Name varchar(100) NOT NULL
and you will see that you are able to modify the Name column to a NOT NULL column using these steps. This is because at this time Sybase server checks as there is no data in the table hence the NOT NULL constraint is not checked and the column is made NOT NULL. Hence, we are able to skip the default constraint.
In case there would have been some data already present in the table Test, then we need to add one more step in between steps 1 and 2 which will add default values to the existing rows in the table. This can be done via a script for previous data and then following the step 2.
To make the column only allow unique values for the column you need to add a unique key constraint using the following syntax -
alter table Test add constraint UK1 unique(Name)

SQL: Create new column with default, unique value

I have added a new column, called Ordinal, to a table called Activity. The problem is that I gave it a UNIQUE constraint, set it to allow NULL (though this I won't want in the end.. I just needed to set it to that to get a little farther with the script), and did not give it a default value. I'm now running a RedGate SQL Compare script that was generated by comparing this table to a version of the Activity table that does not have the column. But I'm getting the following error:
The CREATE UNIQUE INDEX statement terminated because a duplicate key was found for the object name 'iwt.Activity' and the index name 'IX_Activity'. The duplicate key value is (1).
So based on my research, it's trying to create a unique key constraint on the Ordinal column, but NULL is not unique. So my next step was to give it a unique value of 1 just to let the script pass. But 1 isn't going to be unique either. So, finally, my question:
Preferably in SQL Server Management Studio, how do I set a column as having a unique default value? Isn't that what I would need to create this constraint?
Thanks.
try this:
NULL will be the first constraint when you create the column.
UNIQUE will be as add constraint, you should add the second constraint.
they can run on this order with no problem (tested):
--first constraint
alter table Table_Name
add Column_Name int null
--second constraint
alter table Table_Name
add constraint Constraint_Name unique (Column_Name)
In my example :
PaymentGatewayHash is column
Cart is a table
--first query
alter table Cart
add PaymentGatewayHash NVARCHAR(20) null
--second query
CREATE UNIQUE INDEX PaymentGatewayHashUnique
ON Cart (PaymentGatewayHash)
WHERE PaymentGatewayHash IS NOT NULL
I just tested that :D