Making existing fields part of primary key
Hi,
There is a Z table(custom table), which has 3000 records. There are 12 fields in the table out of which 6 of them form the primary key. I need to make 2 more fields in the table part of primary key.
Is that possible? Will it affect the existing data in the table?
Please explain the possible ways of doing it.
Points will be given to all the helful answers.
Thanks- Nobin
Hi,
There can never be a possibility of Data issues. If a record in a table becomes unique by just the 6 fields , then the existing data will remain unique even if you add 2 more fields in the key.
Data issues can only come if you are reducing the key fields.
Take an example of a table with 2 fields and the data as show below
A1 B1
A1 B2
A2 B1
A2 B2
Now in this case if you reduce the key fields and make the first column only as the key then there can be issues as the there will be multiple rows with the same key.
In case you increase the key fields , then since the data was unique, the data will remain unique now also.
A1 B1 C1
A1 B2 C1
A2 B1 C1
A2 B2 C1
Regards,
Aj
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Hello everyone
I need some advice.
I have transp. table ZINVOICE which have data in production system.
field of table are
VBELN Primary key
KUNNR
NAME
FKART
FKDAT
NETWR
STAT
TAXINVNUM
ZFKDAT
ZNETWR
now i want table ZINVOICE have 2 primary (VBELN + TAXINVNUM)
when i activate system show
Key is already defined; field TAXINVNUM cannot be in the key
Message no. AD434
Diagnosis
When defining table fields, you added further key fields at the end after entering a block of key fields followed by a block of non-key fields.
All the key fields of a table must be in a block at the beginning of the table.
Procedure
All key fields in a table should be entered in a single block.
is it mean that primay key must be in beginning of the table ?
can i delete field in table ZINVOICE and insert field and change position of fields to
VBELN Primary key
TAXINVNUM Primary key
KUNNR
NAME
FKART
FKDAT
NETWR
STAT
ZFKDAT
ZNETWR
can i do like this ?
is it impact my existing data in SAP ?
please advice.As you are adding a new key, you should not get problem with duplicate records.
You should create two transport requests and activate/transport the table twice.
- In the first request, change the order of fields in the database table, don't add primary key now, activate , if required adjust database table (should not be required), transport database table in target system.
- In the second request, declare the second field as a primary key, proceed same way.
DON'T TRANSPORT BOTH REQUESTS TOGETHER
First step
VBELN K
TAXINVNUM
KUNNR
NAME
Second step
VBELN K
TAXINVNUM K
KUNNR
NAME
Question: Did you forget to add the client field, if yes you will have to adjust the table and the records will be copied in every client, you will have to create and execute a small cleanup program
Third step
MANDT K
VBELN K
TAXINVNUM K
KUNNR
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Regards,
Raymond -
can i create more than one primary key in database table..?what is the function of primary key compare to foriegn key
Hi
Primary Key:
it is useful to uniquely identify the rows in a table by one or more columns so that you can process them in a specified sequence, for example. You can do this by assigning a primary key. The column names that are to create the table key are represented by the keywords PRIMARY KEY. The input values of the key columns defined in this way must not be a NULL value.
You can use the primary key to insert rows in a table in the same way as you insert rows in a base table when no primary key is defined. However, the system outputs an error message if you attempt to insert an existing value into the primary key column a second time, since the uniqueness of the column is ensured by defining the primary key.
A primary key can consist of multiple columns. However, it is unusual for a key to be constructed from more than five columns, since this makes it difficult for users to enter unique values. The arrangement of the columns behind the keywords PRIMARY KEY defines the key sequence.
Foreign Keys :
You can define the relationships between tables in the ABAP Dictionary by creating foreign keys.
Using foreign keys, you can easily create value checks for input fields. Foreign keys can also be used to link several tables in a view or a lock object.
Reward Points if useful -
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Look at:
Re: Novalidate primary key
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