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The simplest method would be to build a "QueryString" using a ROWID value. An example usage of a ROWID within the SmartBusinessEntityAdapter QueryString statement is given below:
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DEFINE VARIABLE oAdapter AS SmartBusinessEntityAdapter NO-UNDO .
DEFINE VARIABLE roRowid AS ROWID NO-UNDO .
FIND Customer WHERE Customer.CustNum = 10 NO-LOCK NO-ERROR.
IF AVAILABLE Customer THEN
roRowid = ROWID (Customer) .
oAdapter = NEW SmartBusinessEntityAdapter () .
oAdapter:EntityName = "Consultingwerk.SimpleCustomerBusinessEntity.CustomerBusinessEntity":U .
oAdapter:EntityTable = "eCustomer":U .
oAdapter:QueryString = SUBSTITUTE ("for each eCustomer where ROWID (Customer) = TO-ROWID (&1)",
QUOTER (roRowid)) .
oAdapter:RetrieveData ( ) . |
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If we perform a FetchData on our Customer Business Entity, we know that on each record returned, the calculated field shall be populated accordingly. Therefore, it is also possible to perform a Query on the data already contained within our SmartBusinessEntityAdapter.
An example usage of a ROWID within a prepopulated SmartBusinessEntityAdapter is given below:
The first section defines our SmartBusinessEntityAdapter and prepopulates the Adapter with 200 records.
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DEFINE VARIABLE oAdapter AS SmartBusinessEntityAdapter NO-UNDO . DEFINE VARIABLE roRowid AS ROWID NO-UNDO . FIND Customer WHERE Customer.CustNum = 51 NO-LOCK NO-ERROR . roRowid = ROWID (Customer) . oAdapter = NEW SmartBusinessEntityAdapter ( ) . oAdapter:EntityName = "Sports.Customer.CustomerBusinessEntity":U . oAdapter:EntityTable = "eCustomer":U . /* Give client enough records, so that the ROWID in question is available on the client */ oAdapter:BatchSize = 200 . oAdapter:RetrieveData ( ) . |
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The second section shows how to query our current Adapter using the "FindRowWhere" method:
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oAdapter:FindRowWhere (SUBSTITUTE ("where eCustomer.CustomerRowid = TO-ROWID(&1)",
QUOTER (roRowid))).
/* Let's show the FindRowWhere Result */
BufferHelper:ShowBuffer(oAdapter:DATASET::eCustomer:HANDLE).
/* OR */
MESSAGE oAdapter:GetFieldValues("CustNum":U) VIEW-AS ALERT-BOX. |
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Within the "OVERRIDE PUBLIC VOID FetchData" method, we need to construct code that manipulates the Query before calling "SUPER:FetchData(INPUT poFetchDataRequest)".
The FetchData use case is given below:
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METHOD OVERRIDE PUBLIC VOID FetchData ( poFetchDataRequest AS Consultingwerk.OERA.IFetchDataRequest ):
DEFINE VARIABLE cFindString AS CHARACTER NO-UNDO.
DEFINE VARIABLE cRequestContext AS CHARACTER NO-UNDO.
DEFINE VARIABLE oParser AS QueryParser NO-UNDO .
DEFINE VARIABLE oExpression AS IQueryExpression NO-UNDO .
DEFINE VARIABLE oFieldExpression AS QueryExpression NO-UNDO .
ASSIGN cRequestContext = ENTRY (1, poFetchDataRequest:Context, CHR (1)) .
IF NUM-ENTRIES (cRequestContext, CHR (2)) > 1 THEN
ASSIGN cFindString = ENTRY (2, cRequestContext, CHR (2)) .
/* When we're searching for CustomerRowid, we need to turn that into ROWID (Customer) = ... */
IF cFindString > "":U AND INDEX (cFindString, "TO-ROWID (":U) > 0 THEN DO:
cFindString = REPLACE (REPLACE ("for each eCustomer " + cFindString, "TO-ROWID (", ""), ")", "") .
oParser = NEW QueryParser () .
oExpression = oParser:ParseQueryString(cFindString) .
IF QueryExpression:HasExpressionForField("eCustomer.CustomerRowid", oExpression) THEN DO:
oFieldExpression = QueryExpression:GetExpressionForField ("eCustomer.CustomerRowid",
oExpression) .
ASSIGN cFindString = SUBSTITUTE ("WHERE ROWID (Customer) = TO-ROWID (&1)",
QUOTER (CAST (oFieldExpression:SecondOperand,
CharacterHolder):Value)) .
ENTRY (2, cRequestContext, CHR (2)) = cFindString .
ENTRY (1, poFetchDataRequest:Context, CHR (1)) = cRequestContext .
poFetchDataRequest:Context = cRequestContext .
END.
END.
SUPER:FetchData (INPUT poFetchDataRequest).
END METHOD. |
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We are then checking to see if the query contains the Progress Function "TO-ROWID", if so, we know that the query is based on our Calculated Field. We subsequently proceed in replacing Progress Function "TO-ROWID" with an empty string. This is done to avoid the Query Parser parsing and segmenting "TO-ROWID" as another filter block option (e.g EQ, BEGINS). Once we have performed our pre-initial operation, we proceed by checking if the Query expression contains our "CustomerRowid" calculated field. If it does, then we manipulate the query to read as our SmartBusinessEntityAdapter QueryString example.
Note: we are basically replacing the relevant "CustomerRowid" segment of the Query.
Once we have manipulated our Query, we then simply assign the Query back into our FetchDateRequest object.
An example use case for Server Side Filtering is given below:
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DEFINE VARIABLE oAdapter AS SmartBusinessEntityAdapter NO-UNDO .
DEFINE VARIABLE roRowid AS ROWID NO-UNDO .
FIND Customer WHERE Customer.CustNum = 10 NO-LOCK NO-ERROR .
roRowid = ROWID (Customer) .
oAdapter = NEW SmartBusinessEntityAdapter() .
oAdapter:EntityName = "Sports.Customer.CustomerBusinessEntity":U .
oAdapter:EntityTable = "eCustomer":U .
oAdapter:PrefetchOnFindRowWhere = 2 .
/* Give client enough records, so that the ROWID in question is available on the client */
oAdapter:BatchSize = 5 .
oAdapter:RetrieveData ( ) .
oAdapter:FindRowWhere (SUBSTITUTE ("where eCustomer.CustomerRowid = TO-ROWID (&1)",
QUOTER (roRowid)),
FindRowWhereModeEnum:FindOnServerOnly).
/* Let's show the FindRowWhere Result */
BufferHelper:ShowBuffer(oAdapter:DATASET::eCustomer:HANDLE).
/* OR */
MESSAGE oAdapter:GetFieldValues("CustNum":U) VIEW-AS ALERT-BOX. |