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Microsoft OLE DB Provider for Microsoft Jet Overview

The OLE DB Provider for Microsoft Jet allows ADO to access Microsoft Jet databases.

Connection String Parameters

To connect to this provider, set the Provider argument of the ConnectionString property to the following property:

Microsoft.Jet.OLEDB.4.0

Reading the Provider property will also return this string.

Typical Connection String

A typical connection string for this provider is:

"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=databaseName;User ID=MyUserID;Password=MyPassword;"

The string consists of these keywords:

Keyword Description
Provider Specifies the OLE DB Provider for Microsoft Jet.
Data Source Specifies the database path and file name (for example, c:\Northwind.mdb).
User ID Specifies the user name. If this keyword is not specified, the string, "admin", is used by default.
Password Specifies the user password. If this keyword is not specified, the empty string (""), is used by default.

Note

If you are connecting to a data source provider that supports Windows authentication, you should specify Trusted_Connection=yes or Integrated Security = SSPI instead of user ID and password information in the connection string.

Provider-Specific Connection Parameters

The OLE DB Provider for Microsoft Jet supports several provider-specific dynamic properties in addition to those defined by ADO. As with all other Connection parameters, they can be set by using the Properties collection of the Connection object or as part of the connection string.

The following table lists these properties together with the corresponding OLE DB property name in parentheses.

Parameter Description
Jet OLEDB:Compact Reclaimed Space Amount (DBPROP_JETOLEDB_COMPACTFREESPACESIZE) Indicates an estimate of the amount of space, in bytes, that can be reclaimed by compacting the database. This value is only valid after a database connection has been established.
Jet OLEDB:Connection Control (DBPROP_JETOLEDB_CONNECTIONCONTROL) Indicates whether users can connect to the database.
Jet OLEDB:Create System Database (DBPROP_JETOLEDB_CREATESYSTEMDATABASE) Indicates whether a system database should be created when creating a new data source.
Jet OLEDB:Database Locking Mode (DBPROP_JETOLEDB_DATABASELOCKMODE) Indicates the locking mode for this database. The first user to open the database determines the mode used while the database is open.
Jet OLEDB:Database Password (DBPROP_JETOLEDB_DATABASEPASSWORD) Indicates the database password.
Jet OLEDB:Don't Copy Locale on Compact (DBPROP_JETOLEDB_COMPACT_DONTCOPYLOCALE) Indicates whether Jet should copy locale information when compacting a database.
Jet OLEDB:Encrypt Database (DBPROP_JETOLEDB_ENCRYPTDATABASE) Indicates whether a compacted database should be encrypted. If this property is not set, the compacted database will be encrypted if the original database was also encrypted.
Jet OLEDB:Engine Type (DBPROP_JETOLEDB_ENGINE) Indicates the storage engine used to access the current data store.
Jet OLEDB:Exclusive Async Delay (DBPROP_JETOLEDB_EXCLUSIVEASYNCDELAY) Indicates the maximum length of time, in milliseconds, that Jet can delay asynchronous writes to disk when the database is opened exclusively.

This property is ignored unless Jet OLEDB:Flush Transaction Timeout is set to 0.
Jet OLEDB:Flush Transaction Timeout (DBPROP_JETOLEDB_FLUSHTRANSACTIONTIMEOUT) Indicates the amount of time to wait before data stored in a cache for asynchronous writing is written to disk. This setting overrides the values for Jet OLEDB:Shared Async Delay and Jet OLEDB:Exclusive Async Delay.
Jet OLEDB:Global Bulk Transactions (DBPROP_JETOLEDB_GLOBALBULKNOTRANSACTIONS) Indicates whether SQL bulk transactions are transacted.
Jet OLEDB:Global Partial Bulk Ops (DBPROP_JETOLEDB_GLOBALBULKPARTIAL) Indicates the password used to open the database.
Jet OLEDB:Implicit Commit Sync (DBPROP_JETOLEDB_IMPLICITCOMMITSYNC) Indicates whether changes that were made in internal implicit transactions are written in synchronous or asynchronous mode.
Jet OLEDB:Lock Delay (DBPROP_JETOLEDB_LOCKDELAY) Indicates the number of milliseconds to wait before trying to acquire a lock after a previous attempt has failed.
Jet OLEDB:Lock Retry (DBPROP_JETOLEDB_LOCKRETRY) Indicates how many times an attempt to access a locked page is repeated.
Jet OLEDB:Max Buffer Size (DBPROP_JETOLEDB_MAXBUFFERSIZE) Indicates the maximum amount of memory, in kilobytes, Jet can use before it starts flushing changes to disk.
Jet OLEDB:Max Locks Per File (DBPROP_JETOLEDB_MAXLOCKSPERFILE) Indicates the maximum number of locks Jet can place on a database. The default value is 9500.
Jet OLEDB:New Database Password (DBPROP_JETOLEDB_NEWDATABASEPASSWORD) Indicates the new password to be set for this database. The old password is stored in Jet OLEDB:Database Password.
Jet OLEDB:ODBC Command Time Out (DBPROP_JETOLEDB_ODBCCOMMANDTIMEOUT) Indicates the number of milliseconds before a remote ODBC query from Jet will time out.
Jet OLEDB:Page Locks to Table Lock (DBPROP_JETOLEDB_PAGELOCKSTOTABLELOCK) Indicates how many pages must be locked within a transaction before Jet tries to promote the lock to a table lock. If this value is 0, the lock is never promoted.
Jet OLEDB:Page Timeout (DBPROP_JETOLEDB_PAGETIMEOUT) Indicates the number of milliseconds Jet will wait before checking to see whether its cache is out of date with the database file.
Jet OLEDB:Recycle Long-Valued Pages (DBPROP_JETOLEDB_RECYCLELONGVALUEPAGES) Indicates whether Jet should aggressively try to reclaim BLOB pages when they are freed.
Jet OLEDB:Registry Path (DBPROP_JETOLEDB_REGPATH) Indicates the Windows registry key that contains values for the Jet database engine.
Jet OLEDB:Reset ISAM Stats (DBPROP_JETOLEDB_RESETISAMSTATS) Indicates whether the schema Recordset DBSCHEMA_JETOLEDB_ISAMSTATS should reset its performance counters after it returns performance information.
Jet OLEDB:Shared Async Delay (DBPROP_JETOLEDB_SHAREDASYNCDELAY) Indicates the maximum amount of time, in milliseconds, Jet can delay asynchronous writes to disk when the database is opened in multiuser mode.
Jet OLEDB:System Database (DBPROP_JETOLEDB_SYSDBPATH) Indicates the path and file name for the workgroup information file (system database).
Jet OLEDB:Transaction Commit Mode (DBPROP_JETOLEDB_TXNCOMMITMODE) Indicates whether Jet writes data to disk synchronously or asynchronously when a transaction is committed.
Jet OLEDB:User Commit Sync (DBPROP_JETOLEDB_USERCOMMITSYNC) Indicates whether changes that were made in transactions are written in synchronous or asynchronous mode.

Provider-Specific Recordset and Command Properties

The Jet provider also supports several provider-specific Recordset and Command properties. These properties are accessed and set through the Properties collection of the Recordset or Command object. The table lists the ADO property name and its corresponding OLE DB property name in parentheses.

Property Name Description
Jet OLEDB:Bulk Transactions (DBPROP_JETOLEDB_BULKNOTRANSACTIONS) Indicates whether SQL bulk operations are transacted. Large bulk operations might fail when transacted, because of resource delays.
Jet OLEDB:Enable Fat Cursors (DBPROP_JETOLEDB_ENABLEFATCURSOR) Indicates whether Jet should cache multiple rows when populating a recordset for remote row sources.
Jet OLEDB:Fat Cursor Cache Size (DBPROP_JETOLEDB_FATCURSORMAXROWS) Indicates the number of rows to cache when using remote data store row caching. This value is ignored unless Jet OLEDB:Enable Fat Cursors is True.
Jet OLEDB:Inconsistent (DBPROP_JETOLEDB_INCONSISTENT) Indicates whether query results allow inconsistent updates.
Jet OLEDB:Locking Granularity (DBPROP_JETOLEDB_LOCKGRANULARITY) Indicates whether a table is opened using row-level locking.
Jet OLEDB:ODBC Pass-Through Statement (DBPROP_JETOLEDB_ODBCPASSTHROUGH) Indicates that Jet should pass the SQL text in a Command object to the back end unaltered.
Jet OLEDB:Partial Bulk Ops (DBPROP_JETOLEDB_BULKPARTIAL) Indicates Jet's behavior when SQL DML operations fail.
Jet OLEDB:Pass Through Query Bulk-Op (DBPROP_JETOLEDB_PASSTHROUGHBULKOP) Indicates whether queries that do not return a Recordset are passed unaltered to the data source.
Jet OLEDB:Pass Through Query Connect String (DBPROP_JETOLEDB_ODBCPASSTHROUGHCONNECTSTRING) Indicates the Jet connect string used to connect to a remote data store. This value is ignored unless Jet OLEDB:ODBC Pass-Through Statement is True.
Jet OLEDB:Stored Query (DBPROP_JETOLEDB_STOREDQUERY) Indicates whether the command text should be interpreted as a stored query instead of a SQL command.
Jet OLEDB:Validate Rules On Set (DBPROP_JETOLEDB_VALIDATEONSET) Indicates whether the Jet validation rules are evaluated when column data is set or when the changes are committed to the database.

By default, the OLE DB Provider for Microsoft Jet opens Microsoft Jet databases in read/write mode. To open a database in read-only mode, set the Mode property on the ADO Connection object to adModeRead.

Command Object Usage

Command text in the Command object uses the Microsoft Jet SQL dialect. You can specify row-returning queries, action queries, and table names in the command text; however, stored procedures are not supported and should not be specified.

Recordset Behavior

The Microsoft Jet database engine does not support dynamic cursors. Therefore, the OLE DB Provider for Microsoft Jet does not support the adLockDynamic cursor type. When a dynamic cursor is requested, the provider will return a keyset cursor and reset the CursorType property to indicate the type of Recordset returned. Further, if an updatable Recordset is requested (LockType is adLockOptimistic, adLockBatchOptimistic, or adLockPessimistic) the provider will also return a keyset cursor and reset the CursorType property.

Dynamic Properties

The OLE DB Provider for Microsoft Jet inserts several dynamic properties into the Properties collection of the unopened Connection, Recordset, and Command objects.

The following tables are a cross-index of the ADO and OLE DB names for each dynamic property. The OLE DB Programmer's Reference refers to an ADO property name by the term, "Description." You can find more information about these properties in the OLE DB Programmer's Reference.

Connection Dynamic Properties

The following properties are added to the Properties collection of the Connection object.

ADO Property Name OLE DB Property Name
Active Sessions DBPROP_ACTIVESESSIONS
Asynchable Abort DBPROP_ASYNCTXNABORT
Asynchable Commit DBPROP_ASYNCTNXCOMMIT
Autocommit Isolation Levels DBPROP_SESS_AUTOCOMMITISOLEVELS
Catalog Location DBPROP_CATALOGLOCATION
Catalog Term DBPROP_CATALOGTERM
Column Definition DBPROP_COLUMNDEFINITION
Current Catalog DBPROP_CURRENTCATALOG
Data Source DBPROP_INIT_DATASOURCE
Data Source Name DBPROP_DATASOURCENAME
Data Source Object Threading Model DBPROP_DSOTHREADMODEL
DBMS Name DBPROP_DBMSNAME
DBMS Version DBPROP_DBMSVER
GROUP BY Support DBPROP_GROUPBY
Heterogeneous Table Support DBPROP_HETEROGENEOUSTABLES
Identifier Case Sensitivity DBPROP_IDENTIFIERCASE
Isolation Levels DBPROP_SUPPORTEDTXNISOLEVELS
Isolation Retention DBPROP_SUPPORTEDTXNISORETAIN
Locale Identifier DBPROP_INIT_LCID
Maximum Index Size DBPROP_MAXINDEXSIZE
Maximum Row Size DBPROP_MAXROWSIZE
Maximum Row Size Includes BLOB DBPROP_MAXROWSIZEINCLUDESBLOB
Maximum Tables in SELECT DBPROP_MAXTABLESINSELECT
Mode DBPROP_INIT_MODE
Multiple Parameter Sets DBPROP_MULTIPLEPARAMSETS
Multiple Results DBPROP_MULTIPLERESULTS
Multiple Storage Objects DBPROP_MULTIPLESTORAGEOBJECTS
Multi-Table Update DBPROP_MULTITABLEUPDATE
NULL Collation Order DBPROP_NULLCOLLATION
NULL Concatenation Behavior DBPROP_CONCATNULLBEHAVIOR
OLE DB Version DBPROP_PROVIDEROLEDBVER
OLE Object Support DBPROP_OLEOBJECTS
Open Rowset Support DBPROP_OPENROWSETSUPPORT
ORDER BY Columns in Select List DBPROP_ORDERBYCOLUMNSINSELECT
Output Parameter Availability DBPROP_OUTPUTPARAMETERAVAILABILITY
Pass By Ref Accessors DBPROP_BYREFACCESSORS
Password DBPROP_AUTH_PASSWORD
Persistent ID Type DBPROP_PERSISTENTIDTYPE
Prepare Abort Behavior DBPROP_PREPAREABORTBEHAVIOR
Prepare Commit Behavior DBPROP_PREPARECOMMITBEHAVIOR
Procedure Term DBPROP_PROCEDURETERM
Prompt DBPROP_INIT_PROMPT
Provider Friendly Name DBPROP_PROVIDERFRIENDLYNAME
Provider Name DBPROP_PROVIDERFILENAME
Provider Version DBPROP_PROVIDERVER
Read-Only Data Source DBPROP_DATASOURCEREADONLY
Rowset Conversions on Command DBPROP_ROWSETCONVERSIONSONCOMMAND
Schema Term DBPROP_SCHEMATERM
Schema Usage DBPROP_SCHEMAUSAGE
SQL Support DBPROP_SQLSUPPORT
Structured Storage DBPROP_STRUCTUREDSTORAGE
Subquery Support DBPROP_SUBQUERIES
Table Term DBPROP_TABLETERM
Transaction DDL DBPROP_SUPPORTEDTXNDDL
User ID DBPROP_AUTH_USERID
User Name DBPROP_USERNAME
Window Handle DBPROP_INIT_HWND

Recordset Dynamic Properties

The following properties are added to the Properties collection of the Recordset object.

ADO Property Name OLE DB Property Name
Access Order DBPROP_ACCESSORDER
Append-Only Rowset DBPROP_APPENDONLY
Blocking Storage Objects DBPROP_BLOCKINGSTORAGEOBJECTS
Bookmark Type DBPROP_BOOKMARKTYPE
Bookmarkable DBPROP_IROWSETLOCATE
Bookmarks Ordered DBPROP_ORDEREDBOOKMARKS
Cache Deferred Columns DBPROP_CACHEDEFERRED
Change Inserted Rows DBPROP_CHANGEINSERTEDROWS
Column Privileges DBPROP_COLUMNRESTRICT
Column Set Notification DBPROP_NOTIFYCOLUMNSET
Column Writable DBPROP_MAYWRITECOLUMN
Defer Column DBPROP_DEFERRED
Delay Storage Object Updates DBPROP_DELAYSTORAGEOBJECTS
Fetch Backwards DBPROP_CANFETCHBACKWARDS
Hold Rows DBPROP_CANHOLDROWS
IAccessor DBPROP_IAccessor
IColumnsInfo DBPROP_IColumnsInfo
IColumnsRowset DBPROP_IColumnsRowset
IConnectionPointContainer DBPROP_IConnectionPointContainer
IConvertType DBPROP_IConvertType
ILockBytes DBPROP_ILockBytes
Immobile Rows DBPROP_IMMOBILEROWS
IRowset DBPROP_IRowset
IRowsetChange DBPROP_IRowsetChange
IRowsetIdentity DBPROP_IRowsetIdentity
IRowsetIndex DBPROP_IRowsetIndex
IRowsetInfo DBPROP_IRowsetInfo
IRowsetLocate DBPROP_IRowsestLocate
IRowsetResynch
IRowsetScroll DBPROP_IRowsetScroll
IRowsetUpdate DBPROP_IRowsetUpdate
ISequentialStream DBPROP_ISequentialStream
IStorage DBPROP_IStorage
IStream DBPROP_IStream
ISupportErrorInfo DBPROP_ISupportErrorInfo
Literal Bookmarks DBPROP_LITERALBOOKMARKS
Literal Row Identity DBPROP_LITERALIDENTITY
Maximum Open Rows DBPROP_MAXOPENROWS
Maximum Pending Rows DBPROP_MAXPENDINGROWS
Maximum Rows DBPROP_MAXROWS
Memory Usage DBPROP_MEMORYUSAGE
Notification Granularity DBPROP_NOTIFICATIONGRANULARITY
Notification Phases DBPROP_NOTIFICATIONPHASES
Objects Transacted DBPROP_TRANSACTEDOBJECT
Others' Changes Visible DBPROP_OTHERUPDATEDELETE
Others' Inserts Visible DBPROP_OTHERINSERT
Own Changes Visible DBPROP_OWNUPDATEDELETE
Own Inserts Visible DBPROP_OWNINSERT
Preserve on Abort DBPROP_ABORTPRESERVE
Preserve on Commit DBPROP_COMMITPRESERVE
Quick Restart DBPROP_QUICKRESTART
Reentrant Events DBPROP_REENTRANTEVENTS
Remove Deleted Rows DBPROP_REMOVEDELETED
Report Multiple Changes DBPROP_REPORTMULTIPLECHANGES
Return Pending Inserts DBPROP_RETURNPENDINGINSERTS
Row Delete Notification DBPROP_NOTIFYROWDELETE
Row First Change Notification DBPROP_NOTIFYROWFIRSTCHANGE
Row Insert Notification DBPROP_NOTIFYROWINSERT
Row Privileges DBPROP_ROWRESTRICT
Row Resynchronization Notification DBPROP_NOTIFYROWRESYNCH
Row Threading Model DBPROP_ROWTHREADMODEL
Row Undo Change Notification DBPROP_NOTIFYROWUNDOCHANGE
Row Undo Delete Notification DBPROP_NOTIFYROWUNDODELETE
Row Undo Insert Notification DBPROP_NOTIFYROWUNDOINSERT
Row Update Notification DBPROP_NOTIFYROWUPDATE
Rowset Fetch Position Change Notification DBPROP_NOTIFYROWSETFETCHPOSISIONCHANGE
Rowset Release Notification DBPROP_NOTIFYROWSETRELEASE
Scroll Backwards DBPROP_CANSCROLLBACKWARDS
Skip Deleted Bookmarks DBPROP_BOOKMARKSKIPPED
Strong Row Identity DBPROP_STRONGITDENTITY
Updatability DBPROP_UPDATABILITY
Use Bookmarks DBPROP_BOOKMARKS

Command Dynamic Properties

The following properties are added to the Properties collection of the Command object.

ADO Property Name OLE DB Property Name
Access Order DBPROP_ACCESSORDER
Append-Only Rowset DBPROP_APPENDONLY
Blocking Storage Objects DBPROP_BLOCKINGSTORAGEOBJECTS
Bookmark Type DBPROP_BOOKMARKTYPE
Bookmarkable DBPROP_IROWSETLOCATE
Change Inserted Rows DBPROP_CHANGEINSERTEDROWS
Column Privileges DBPROP_COLUMNRESTRICT
Column Set Notification DBPROP_NOTIFYCOLUMNSET
Defer Column DBPROP_DEFERRED
Delay Storage Object Updates DBPROP_DELAYSTORAGEOBJECTS
Fetch Backwards DBPROP_CANFETCHBACKWARDS
Hold Rows DBPROP_CANHOLDROWS
IAccessor DBPROP_IAccessor
IColumnsInfo DBPROP_IColumnsInfo
IColumnsRowset DBPROP_IColumnsRowset
IConnectionPointContainer DBPROP_IConnectionPointContainer
IConvertType DBPROP_IConvertType
ILockBytes DBPROP_ILockBytes
Immobile Rows DBPROP_IMMOBILEROWS
IRowset DBPROP_IRowset
IRowsetChange DBPROP_IRowsetChange
IRowsetIdentity DBPROP_IRowsetIdentity
IRowsetIndex DBPROP_IRowsetIndex
IRowsetInfo DBPROP_IRowsetInfo
IRowsetLocate DBPROP_IRowsetLocate
IRowsetResynch
IRowsetScroll DBPROP_IRowsetScroll
IRowsetUpdate DBPROP_IRowsetUpdate
ISequentialStream DBPROP_ISequentialStream
IStorage DBPROP_IStorage
IStream DBPROP_IStream
ISupportErrorInfo DBPROP_ISupportErrorInfo
Literal Bookmarks DBPROP_LITERALBOOKMARKS
Literal Row Identity DBPROP_LITERALIDENTITY
Lock Mode DBPROP_LOCKMODE
Maximum Open Rows DBPROP_MAXOPENROWS
Maximum Pending Rows DBPROP_MAXPENDINGROWS
Maximum Rows DBPROP_MAXROWS
Notification Granularity DBPROP_NOTIFICATIONGRANULARITY
Notification Phases DBPROP_NOTIFICATIONPHASES
Objects Transacted DBPROP_TRANSACTEDOBJECT
Others' Changes Visible DBPROP_OTHERUPDATEDELETE
Others' Inserts Visible DBPROP_OTHERINSERT
Own Changes Visible DBPROP_OWNUPDATEDELETE
Own Inserts Visible DBPROP_OWNINSERT
Preserve on Abort DBPROP_ABORTPRESERVE
Preserve on Commit DBPROP_COMMITPRESERVE
Quick Restart DBPROP_QUICKRESTART
Reentrant Events DBPROP_REENTRANTEVENTS
Remove Deleted Rows DBPROP_REMOVEDELETED
Report Multiple Changes DBPROP_REPORTMULTIPLECHANGES
Return Pending Inserts DBPROP_RETURNPENDINGINSERTS
Row Delete Notification DBPROP_NOTIFYROWDELETE
Row First Change Notification DBPROP_NOTIFYROWFIRSTCHANGE
Row Insert Notification DBPROP_NOTIFYROWINSERT
Row Privileges DBPROP_ROWRESTRICT
Row Resynchronization Notification DBPROP_NOTIFYROWRESYNCH
Row Threading Model DBPROP_ROWTHREADMODEL
Row Undo Change Notification DBPROP_NOTIFYROWUNDOCHANGE
Row Undo Delete Notification DBPROP_NOTIFYROWUNDODELETE
Row Undo Insert Notification DBPROP_NOTIFYROWUNDOINSERT
Row Update Notification DBPROP_NOTIFYROWUPDATE
Rowset Fetch Position Change Notification DBPROP_NOTIFYROWSETFETCHPOSITIONCHANGE
Rowset Release Notification DBPROP_NOTIFYROWSETRELEASE
Scroll Backwards DBPROP_CANSCROLLBACKWARDS
Server Data on Insert DBPROP_SERVERDATAONINSERT
Skip Deleted Bookmarks DBPROP_BOOKMARKSKIP
Strong Row Identity DBPROP_STRONGIDENTITY
Updatability DBPROP_UPDATABILITY
Use Bookmarks DBPROP_BOOKMARKS

For specific implementation details and functional information about the OLE DB Provider for Microsoft Jet, see Jet Provider in the OLE DB documentation.