function
|
Library: Database access (OMDB legacy)
Include: omdb.xin |
Returns: a specific procedure of type |
define external dbProcedure function
dbProcedureOpen value dbDatabase database
procedure value stream procedure
parameter-types read-only integer parameters optional
data-types read-only integer datatypes optional
data-sizes read-only integer datasize optional
Argument definitions
dbDatabase object representing an open database connection.
Use dbProcedureOpen to open a connection to a stored procedure in the database.
You must include the following line at the beginning of your OmniMark program:
include "omdb.xin"
procedure must:
With some ODBC drivers, you must supply all three procedure parameter description arguments (else external exception OMDB409) if your procedure uses parameters. The procedure parameter description shelves (parameters, datatypes and datasizes) must
The parameter types must be valid (else external exception OMDB403). The following macro-defined parameter types are allowed:
Values supplied for datasizes cannot be negative numbers (else external exception OMDB412).
The key names of output parameters are used to key the "out" dbField parameter in dbProcedureExecute.
The following SQL datatypes are supported by this function:
In this example, a stored procedure that processes a customer purchase transaction is executed in the OmniMark program. The stored procedure, "PurchaseItem", takes four parameters:
The first two parameters are only read by the procedure. The ItemCount parameter is read in the procedure and
the total number of items sold to the customer is written into the variable at the end of the procedure. If
there are fewer than the requested number of items in inventory, the written value will be less than the
initial value. The inventory count is only written to by the procedure and it contains the total number of
items remaining in inventory after the sale. The procedure also returns a value. (This type of stored
procedure is called a stored function on some databases.) The value returned is the total cost to the customer
for the purchase.
; process parameter values
local stream CustomerID initial { '7734' }
local stream ProductID initial { '34-RTS-485643' }
local stream ItemCount initial { '47' }
; local variables
local dbProcedure purchase-item
local stream in-val variable
local dbField out-val variable
local dbField res-val variable
local integer types variable initial { SQL_RETURN_VALUE with key 'RETURN_VALUE',
SQL_PARAM_INPUT with key 'CustomerID',
SQL_PARAM_INPUT with key 'ProductID',
SQL_PARAM_INPUT_OUTPUT with key 'ItemCount',
SQL_PARAM_OUTPUT with key 'InventoryCount' }
local integer datatypes variable initial { SQL_DOUBLE with key 'RETURN_VALUE',
SQL_DECIMAL with key 'CustomerID',
SQL_VARCHAR with key 'ProductID',
SQL_DECIMAL with key 'ItemCount',
SQL_DECIMAL with key 'InventoryCount' }
local integer datasizes variable initial { 15 with key 'RETURN_VALUE',
38 with key 'CustomerID',
50 with key 'ProductID',
38 with key 'ItemCount',
38 with key 'InventoryCount' }
; open the procedure
set purchase-item to dbProcedureOpen inventory-db
procedure 'PurchaseItem'
parameter-types types
data-types datatypes
data-sizes datasizes
; set the input values
set new in-val{ 'CustomerID' } to '7734'
set new in-val{ 'ProductID' } to '34-RTS-485643'
set new in-val{ 'ItemCount' } to '47'
; execute the procedure
dbProcedureExecute purchase-item in in-val out out-val result res-val
; display the processing results
output 'Customer %g(CustomerID '
|| 'requested %g(ItemCount) '
|| 'units of %g(ProductID)%n'
output dbFieldValue out-val{ 'ItemCount' }
|| ' units were sold%n'
output dbFieldValue out-val{ 'InventoryCount' }
|| ' units remaining in inventory%n'
output 'Total value of the sale was $'
|| dbFieldValue res-val{'RETURN_VALUE'}
|| '%n'