lock obj

[Former Member]

i know the name of lock obj ,ang fun mod used in lock obj.

any one please help how to use lock obj in real time with good scenario.

(pls dont copy paste theory).

points assured

[Former Member]

Hi Rs,

Good!

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.

Hope this will give a basic idea.

Here is a Link with good example

Look the following Links for additionl info.

http://help.sap.com/saphelp_nw04/helpdata/en/c2/2d7037ecc92a7ee10000009b38f8cf/content.htm

http://help.sap.com/saphelp_nw70/helpdata/en/cf/21eea5446011d189700000e8322d00/content.htm

http://articles.techrepublic.com.com/5100-6329_11-5066352.html

Hope this Helps

Thanks,

Sunil

[Former Member]

Hi

when ever you modify are do some operations on database tables then you need to lock the table before updation and unlock after doing that

so the locking and locking a table can be done in this way

locking

constants: lc_tabname TYPE rstable-tabname VALUE 'FKKVKP' . "FKKVKP

CALL FUNCTION 'ENQUEUE_E_TABLE'

EXPORTING

tabname = lc_tabname

EXCEPTIONS

foreign_lock = 1

system_failure = 2

OTHERS = 3.

unclockin

CALL FUNCTION 'DEQUEUE_E_TABLE'

EXPORTING

TABNAME = lc_tabname .

this is with out useing LOCKOBJECTs

i had done in real time

[Former Member]

Hi,

check if this gives u an idea.

&----

---

*& Report ZLOCKING *

*& *

&----

---

*& *

*& *

&----

---

REPORT zlocking .

DATA : tab_emp TYPE TABLE OF zemp_51772,

wa_emp TYPE zemp_51772.

wa_emp-emp_no = '102'.

wa_emp-emp_id = '157'.

wa_emp-emp_name = 'SIVA'.

wa_emp-emp_dept = 'SAP'.

APPEND wa_emp TO tab_emp.

CLEAR wa_emp.

wa_emp-emp_no = '128'.

wa_emp-emp_id = '138'.

wa_emp-emp_name = 'RAMA'.

wa_emp-emp_dept = 'SAP'.

APPEND wa_emp TO tab_emp.

CLEAR wa_emp.

wa_emp-emp_no = '133'.

wa_emp-emp_id = '121'.

wa_emp-emp_name = 'KRISHNA'.

wa_emp-emp_dept = 'SAP'.

APPEND wa_emp TO tab_emp.

CLEAR wa_emp.

CALL FUNCTION 'ENQUEUE_E_TABLEE'

EXPORTING

mode_rstable = 'X'

tabname = 'ZEMP_51772'

• varkey =

• X_TABNAME = ' '

• X_VARKEY = ' '

• _SCOPE = '2'

• _WAIT = ' '

• _COLLECT = ' '

EXCEPTIONS

foreign_lock = 1

system_failure = 2

OTHERS = 3

.

IF sy-subrc EQ 0.

INSERT zemp_51772 FROM TABLE tab_emp.

ENDIF.

CALL FUNCTION 'DEQUEUE_E_TABLEE'

EXPORTING

mode_rstable = 'X'

tabname = 'ZEMP_51772'

• VARKEY =

• X_TABNAME = ' '

• X_VARKEY = ' '

• _SCOPE = '3'

• _SYNCHRON = ' '

• _COLLECT = ' '

.

IF sy-subrc EQ 0.

WRITE:/ 'Unlocked the Table'.

ENDIF.

ock 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.

Normally ABAPers will create the Lock objects, because we know when to lock and how to lock and where to lock the Object then after completing our updations we unlock the Objects in the Tables

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

purpose: If multiple user try to access a database object, inconsistency may occer. To avoid that inconsistency and to let multiple user give the accessibility of the database objects the locking mechanism is used.

Steps: first we create a loc object in se11 . Suppose for a table mara. It will create two functional module.:

1. enque_lockobject

1. deque_lockobject

before updating any table first we lock the table by calling enque_lockobject fm and then after updating we release the lock by deque_lockobject.

http://help.sap.com/saphelp_nw04/helpdata/en/cf/21eea5446011d189700000e8322d00/content.htm

GO TO SE11

Select the radio button "Lock object"..

Give the name starts with EZ or EY..

Example: EYTEST

Press Create button..

Give the short description..

Example: Lock object for table ZTABLE..

In the tables tab..Give the table name..

Example: ZTABLE

Save and generate..

Your lock object is now created..You can see the LOCK MODULES..

In the menu ..GOTO -> LOCK MODULES..There you can see the ENQUEUE and DEQUEUE function

Lock objects:

http://www.sap-img.com/abap/type-and-uses-of-lock-objects-in-sap.htm

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

Match Code Objects:

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

http://searchsap.techtarget.com/tip/0,289483,sid21_gci553386,00.html

See this link:

http://www.sap-img.com/abap/type-and-uses-of-lock-objects-in-sap.htm

Check these links -