Runs an action query or executes an SQL statement on a specified Connection or Database object.
Syntax
object.Execute source, options
querydef.Execute options
The Execute method syntax has these parts.
Part |
Description |
object |
A Connection or Database object variable on which the query will run. |
querydef |
An object variable that represents the QueryDef object whose SQL property setting specifies the SQL statement to execute. |
source |
A String that is an SQL statement or the Name property value of a QueryDef object. |
options |
Optional. A constant or combination of constants that determines the data integrity characteristics of the query, as specified in Settings. |
Settings
You can use the following constants for options.
Constant |
Description |
dbDenyWrite |
Denies write permission to other users (Microsoft Jet workspaces only). |
dbInconsistent |
(Default) Executes inconsistent updates (Microsoft Jet workspaces only). |
dbConsistent |
Executes consistent updates (Microsoft Jet workspaces only). |
dbSQLPassThrough |
Executes an SQL pass-through query. Setting this option passes the SQL statement to an ODBC database for processing (Microsoft Jet workspaces only). |
dbFailOnError |
Rolls back updates if an error occurs (Microsoft Jet workspaces only). |
dbSeeChanges |
Generates a run-time error if another user is changing data you are editing (Microsoft Jet workspaces only). |
dbRunAsync |
Executes the query asynchronously (ODBCDirect Connection and QueryDef objects only). |
dbExecDirect |
Executes the statement without first calling SQLPrepare ODBC API function (ODBCDirect Connection and QueryDef objects only). |
Note The constants dbConsistent and dbInconsistent are mutually exclusive. You can use one or the other, but not both in a given instance of OpenRecordset. Using both dbConsistent and dbInconsistent causes an error.
Remarks
The Execute method is valid only for action queries. If you use Execute with another type of query, an error occurs. Because an action query doesn't return any records, Execute doesn't return a Recordset. (Executing an SQL pass-through query in an ODBCDirect workspace will not return an error if a Recordset isn't returned.)
Use the RecordsAffected property of the Connection, Database, or QueryDef object to determine the number of records affected by the most recent Execute method. For example, RecordsAffected contains the number of records deleted, updated, or inserted when executing an action query. When you use the Execute method to run a query, the RecordsAffected property of the QueryDef object is set to the number of records affected.
In a Microsoft Jet workspace, if you provide a syntactically correct SQL statement and have the appropriate permissions, the Execute method won't fail — even if not a single row can be modified or deleted. Therefore, always use the dbFailOnError option when using the Execute method to run an update or delete query. This option generates a run-time error and rolls back all successful changes if any of the records affected are locked and can't be updated or deleted.
In earlier versions of the Microsoft Jet Database Engine, SQL statements were automatically embedded in implicit transactions. If part of a statement executed with dbFailOnError failed, the entire statement would be rolled back. To improve performance, these implicit transactions were removed starting with version 3.5. If you are updating older DAO code, be sure to consider using explicit transactions around Execute statements.
For best performance in a Microsoft Jet workspace, especially in a multiuser environment, nest the Execute method inside a transaction. Use the BeginTrans method on the current Workspace object, then use the Execute method, and complete the transaction by using the CommitTrans method on the Workspace. This saves changes on disk and frees any locks placed while the query is running.
In an ODBCDirect workspace, if you include the optional dbRunAsync constant, the query runs asynchronously. To determine whether an asynchronous query is still executing, check the value of the StillExecuting property on the object from which the Execute method was called. To terminate execution of an asynchronous Execute method call, use the Cancel method.
For ODBCDirect, use single quotes to signify strings or an error will be returned.