error for BAPI and BDC

Hi,

recently i am doing material upload prog. i use BAPI to create and extent material, then i use BDC to fill a field inspection type in QM view.

but i am very confused that the result is variable. When i extent material cross plants. one material have extent all plants, but another just extent some> The code is as follow.

LOOP AT IT_MATMASTER.

• transfer BAPI data

BAPIMATHEAD-MATERIAL = IT_MATMASTER-MATNR.

BAPIMATHEAD-IND_SECTOR = IT_MATMASTER-Mbrsh.

BAPIMATHEAD-MATL_TYPE = IT_MATMASTER-Mtart.

........

CALL FUNCTION 'BAPI_MATERIAL_SAVEDATA'

EXPORTING

headdata = BAPIMATHEAD

CLIENTDATA = BAPI_MARA

CLIENTDATAX = BAPI_MARAx

PLANTDATA = BAPI_MARc

PLANTDATAX = BAPI_MARcx

VALUATIONDATA = BAPI_MBEW

VALUATIONDATAX = BAPI_MBEWX

IMPORTING

RETURN = IT_RETURN

TABLES

MATERIALDESCRIPTION = IT_MATERIALDESC.

CALL FUNCTION 'BAPI_TRANSACTION_COMMIT'.

commit work and wait. * create the material

• extent material cross plants

LOOP AT IT_GOUJIAN where WERKS ne IT_MATMASTER-WERKS.

" it_goujian contains plants data

BAPI_MARC-PLANT = IT_GOUJIAN-WERKS.

BAPI_MARCX-PLANT = IT_GOUJIAN-WERKS.

BAPI_MBEW-VAL_AREA = IT_GOUJIAN-WERKS.

BAPI_MBEWX-VAL_AREA = IT_GOUJIAN-WERKS.

CALL FUNCTION 'BAPI_MATERIAL_SAVEDATA'

EXPORTING

headdata = BAPIMATHEAD

CLIENTDATA = BAPI_MARA

CLIENTDATAX = BAPI_MARAx

PLANTDATA = BAPI_MARc

PLANTDATAX = BAPI_MARcx

VALUATIONDATA = BAPI_MBEW

VALUATIONDATAX = BAPI_MBEWX

IMPORTING

RETURN = IT_RETURN

TABLES

MATERIALDESCRIPTION = IT_MATERIALDESC.

CALL FUNCTION 'BAPI_TRANSACTION_COMMIT'.

commit work and wait.

ENDLOOP.

......

endloop.

as u see, the code is correct, the reason just before i can not control the process in SAP. although i use 'commit work and wait.' But sometimes it still dose not extent all plants in the table 'it_goujian'.

any help?? i expect ...