Maintaining and Creating Data Dictionary Objects

[Former Member]

Maintaining and Creating Data Dictionary Objects:-

What are the topics comes under above mentioned header.

[Former Member]

Hi Abhay,

Transaction SE11 will have list of all these objects.

Reward points if useful.

Regards,

Atish

[Former Member]

hi abhay,

following topics can cover under data dictionary,,

creating Data Base tables,

creating structures,dataelements.table types and domians,

creating search helps and views.

then creating lock objects and types...

all these we can develop and maintain in data dictionary (se11).

regards..

seshu.

[Former Member]

Hi

Tables,

Views,

Lock Objects,

Search helps

Data Types( dataelements,Structures)

Domains

Type Groups

The following are the table types used in SAP :

I. Transparent tables (BKPF, VBAK, VBAP, KNA1, COEP)

Allows secondary indexes (SE11->Display Table->Indexes)

Can be buffered (SE11->Display Table->technical settings) Heavily updated tables should not be buffered.

II. Pool Tables (match codes, look up tables)

Should be accessed via primary key or

Should be buffered (SE11->Display Table->technical settings)

No secondary indexes

Select * is Ok because all columns retrieved anyway

III. Cluster Tables (BSEG,BSEC)

Should be accessed via primary key - very fast retrieval otherwise very slow

No secondary indexes

Select * is Ok because all columns retrieved anyway. Performing an operation on multiple rows is more efficient than single row operations. Therefore you still want to select into an internal table. If many rows are being selected into the internal table, you might still like to retrieve specific columns to cut down on the memory required.

Statistical SQL functions (SUM, AVG, MIN, MAX, etc) not supported

Can not be buffered

IV. Buffered Tables (includes both Transparent & Pool Tables)

While buffering database tables in program memory (SELECT into internal table) is generally a good idea for performance, it is not always necessary. Some tables are already buffered in memory. These are mostly configuration tables. If a table is already buffered, then a select statement against it is very fast. To determine if a table is buffered, choose the 'technical settings' soft button from the data dictionary display of a table (SE12). Pool tables should all be buffered.

Tables Documentation

https://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/25c1f5d1-0901-0010-d495-e96d02a0...

Lock objects are use in SAP to avoid the inconsistancy at the time of data is being insert/change into database.

SAP Provide three type of Lock objects.

- Read Lock(Shared Locked)

protects read access to an object. The read lock allows other transactions read access but not write access to

the locked area of the table

- Write Lock(exclusive lock)

protects write access to an object. The write lock allows other transactions neither read nor write access to

the locked area of the table.

- Enhanced write lock (exclusive lock without cumulating)

works like a write lock except that the enhanced write lock also protects from further accesses from the

same transaction.

You can create a lock on a object of SAP thorugh transaction SE11 and enter any meaningful name start with EZ Example EZTEST_LOCK.

Use: you can see in almost all transaction when you are open an object in Change mode SAP could not allow to any other user to open the same object in change mode.

Example: in HR when we are enter a personal number in master data maintainance screen SAP can't allow to any other user to use same personal number for changes.

Technicaly:

When you create a lock object System automatically creat two function module.

1. ENQUEUE_<Lockobject name>. to insert the object in a queue.

2. DEQUEUE_<Lockobject name>. To remove the object is being queued through above FM.

You have to use these function module in your program.

check this link for example.

http://help.sap.com/saphelp_nw04s/helpdata/en/cf/21eea5446011d189700000e8322d00/content.htm

tables:vbak.

call function 'ENQUEUE_EZLOCK3'

exporting

mode_vbak = 'E'

mandt = sy-mandt

vbeln = vbak-vbeln

• X_VBELN = ' '

• _SCOPE = '2'

• _WAIT = ' '

• _COLLECT = ' '

• EXCEPTIONS

• FOREIGN_LOCK = 1

• SYSTEM_FAILURE = 2

• OTHERS = 3

.

if sy-subrc <> 0.

• MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO

• WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.

endif.

1) Elementary search helps describe a search path. The elementary search help must define where the data of the hit list should be read from (selection method), how the exchange of values between the screen template and selection method is implemented (interface of the search help) and how the online input help should be defined (online behavior of the search help).

2) Collective search helps combine several elementary search helps. A collective search help thus can offer several alternative search paths.

3)An elementary search help defines the standard flow of an input help.

4) A collective search help combines several elementary search helps. The user can thus choose one of several alternative search paths with a collective search help.

5)A collective search help comprises several elementary search helps. It combines all the search paths that are meaningful for a field.

6)Both elementary search helps and other search helps can be included in a collective search help. If other collective search helps are contained in a collective search help, they are expanded to the level of the elementary search helps when the input help is called.

http://help.sap.com/saphelp_nw04/helpdata/en/cf/21ee38446011d189700000e8322d00/content.htm

http://help.sap.com/saphelp_nw04/helpdata/en/cf/21ee45446011d189700000e8322d00/content.htm

pls go through this for search help creation

http://help.sap.com/saphelp_nw2004s/helpdata/en/41/f6b237fec48c67e10000009b38f8cf/content.htm

Search Help Exits:

Reward points if useful

Regards

Anji

[former_member196299]

Hi Abhay ,

You can create man maintain Data Dictionary objects under transaction se11 and SE16 ... you will see a list of DDIC objects in SE11.click on f1 and get the further details about the objects .

You can use treansaction sm30 for generating table maintenance generator for operations linked to tables .

Please revert back for further informations with detail questions !

Regards,

Ranjita

[Former Member]

Hai,

The following are the objects of data dictionary I hope this documentation will help you out..

• Table: is a 2D data matrix containing rows and columns. Rows contain data while column indicates fields. Table can contain 0 or multiple rows.

• Structure: is a skeletal view of a table. It contains the definition of columns and don’t have any contents. Structure is generally a template based on which a table is created. The basic difference between structure and table is that the structure does not exist at the underlying database system level. Structure exists as definition in the dictionary.

• Views: A view is an imaginary table. It contains data, which is really stored in other tables. The contents for the view are dynamically generated when called from program.

• Data element: is definition of the properties and type for a table field. It is an intermediate object between the object type domain and the table field. A field in R/3 system is always associated with a data element, which at the same time is related to domain.

• Domain: is formal definition of the data type from a technical point of view. It sets the attributes such as data type, length, possible value range and so on.

• Lock objects: These types of objects are used for locking the access to database records in table. This mechanism is used to enforce data integrity that is two users cannot update the same data at the same time. With lock objects you can lock table-field or whole table.

• Search Help Objects: , which gives list of possible values for either primary keys or non-primary keys.