The information in this article applies to:
- Professional and Enterprise Editions of Microsoft Visual Basic,
16-bit and 32-bit, for Windows, version 4.0
SUMMARY
This article describes how to call Microsoft SQL stored procedures from
Microsoft Visual Basic for Windows. A stored procedure is a precompiled
collection of SQL statements, often including control-of-flow language.
MORE INFORMATION
The method of calling depends on whether the SQL stored procedure returns
records or not. For example:
- Stored procedures that do not return records (or rows) can be executed
from Visual Basic with the ExecuteSQL() method as follows:
i% = MyDb.ExecuteSQL("sp_name")
This executes the stored procedure sp_name and returns the affected
number of rows in i%. The ExecuteSQL method is strictly for action
queries such as:
Delete Authors where name like "fred%"
The ExecuteSQL() method is valid only for SQL statements that do not
return records (or rows). An SQL statement that uses "SELECT..." returns
records, while an SQL statement that uses "DELETE..." does not. Neither
Execute() nor ExecuteSQL() return a recordset, so using ExecuteSQL() on
a query that selects records produces an error.
- Stored procedures that return records (or rows) require a Dynaset or
Snapshot to capture the values. Listed below are two examples:
Example Using a Data Control on a Visual Basic Form:
Data1.Options = dbSQLPassThrough
Data1.Recordsource = "sp_name" ' name of the stored procedure.
Data1.Refresh ' Refresh the data control.
When you use the SqlPassThrough bit, Visual Basic's Microsoft Access
database engine ignores the syntax used and passes the command
through to the SQL server.
Alternative Example Using Object Variables:
Dim Ds as Recordset
' Open your desired database here.
Set MyDB = DBEngine.Workspaces(0).OpenDatabase(...
Set Ds = MyDB.OpenRecordset("sp_name", dbOpenDynaset, _
dbSQLPassThrough)
You can also use 'dbOpenSnapshot' in place of 'dbOpenDynaset' above.
How to Pass Parameters to a Stored Procedure
--------------------------------------------
To pass parameters, include them after the name of the stored procedure
in a string. For example:
' String specifying SQL.
command.SQLx = "My_StorProc parm1, parm2, parm3"
...
' For stored procedure that doesn't return records.
i = MyDB.ExecuteSQL(SQLx)
...
'For stored procedure that returns records.
set Ds = MyDB.OpenRecordset(SQLx, dbOpenDynaset, dbSQLPassThrough)
The object variable (Ds) contains the first set of results from the
stored procedure (My_StorProc).
Another Example
---------------
The following contains more example code showing both methods:
Dim db as Database
Dim l as Long
Dim Ss as Recordset
Set Db = DBEngine.Workspaces(0).OpenDatabase _
("", False, False, "ODBC;dsn=yourdsn;uid=youruid;pwd=yourpwd:")
' For SPs that don't return rows.
l=Db.ExecuteSQL("YourSP_Name")
' For SPs that return rows.
Set Ss = Db.OpenRecordset("YourSP_Name", dbOpenSnapshot, _
dbSQLPassThrough)
Col1.text = Ss(0) ' Column one.
Col2.text = Ss!ColumnName
Col3.Text=Ss("ColumnName")
REFERENCES
More information about calling stored procedures is documented in the
following Microsoft SQL manual which covers the Visual Basic Library for
SQL Server:
- "Microsoft SQL Server Programmer's Reference for Visual Basic"
See the functions SqlRpcInit% (pages 200-201), SqlRpcParam%, and
SqlRpcSend%. These functions call stored procedures more quickly than do
the methods described above.
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