Open Method (Recordset) ADO

Opens a cursor.

Applies To

Recordset

Required Files

msado15.dll
VC: adoint.h, adoid.h

Syntax

recordset.Open Source, ActiveConnection, CursorType, LockType, Options

Source Optional. A Variant that evaluates to a valid Command object variable name, an SQL statement, a table name, or a stored procedure call.
ActiveConnection Optional. A Variant that evaluates to a valid Connection object variable name or a String containing a definition for a connection.
CursorType Optional. A CursorTypeEnum value that determines the type of cursor that the provider should use when opening the Recordset. Can be one of the following constants:
  • adOpenForwardOnly, 0 (Default)

  • adOpenKeyset, 1

  • adOpenDynamic, 2

  • adOpenStatic, 3
See the CursorType property for definitions of these settings.
LockType Optional. A LockTypeEnum value that determines what type of locking (concurrency) the provider should use when opening the Recordset. Can be one of the following constants:
  • adLockReadOnly, 1

  • adLockPessimistic, 2

  • adLockOptimistic, 3

  • adLockBatchOptimistic, 4
See the LockType property for definitions of these settings.
Options Optional. A CommandTypeEnum value that indicates how the provider should evaluate the Source argument if it represents something other than a Command object. Can be one of the following constants:
  • adCmdText, 1 — Evaluate Source as a textual definition of a command.

  • adCmdTable, 2 — Evaluate Source as a table name.

  • adCmdStoredProc, 4 — Evaluate Source as a stored procedure.

  • adCmdUnknown, 8 — The type of command in the Source argument is not known.
See the CommandType property for a more detailed explanation of these constants.

Remarks

Using the Open method on a Recordset object opens a cursor that represents records from a base table or the results of a query.

Use the optional Source argument to specify a data source using one of the following: a Command object variable, an SQL statement, a stored procedure, or a table name.

The ActiveConnection argument corresponds to the ActiveConnection property and specifies in which connection to open the Recordset object. If you pass a connection definition for this argument, ADO opens a new connection using the specified parameters.

For the arguments that correspond directly to properties of a Recordset object (Source, ActiveConnection, CursorType, and LockType), the relationship of the arguments to the properties is as follows:

Note For Recordset objects whose Source property is set to a valid Command object, the ActiveConnection property is read-only, even if the Recordset object isn't open.

If you pass a Command object in the Source argument and also pass an ActiveConnection argument, an error occurs. The ActiveConnection property of the Command object must already be set to a valid Connection object or connection string.

If you pass something other than a Command object in the Source argument, you can use the Options argument to optimize evaluation of the Source argument. If the Options argument is not defined, you may experience diminished performance because ADO must make calls to the provider to determine if the argument is an SQL statement, a stored procedure, or a table name. If you know what Source type you're using, setting the Options argument instructs ADO to jump directly to the relevant code. If the Options argument does not match the Source type, an error occurs.

If the data source returns no records, the provider sets both the BOF and EOF properties to True, and the current record position is undefined. You can still add new data to this empty Recordset object if the cursor type allows it.

When you have concluded your operations over an open Recordset object, use the Close method to free any associated system resources. Closing an object does not remove it from memory; you may change its property settings and use the Open method to open it again later. To completely eliminate an object from memory, set the object variable to Nothing.

Examples

Open and Close Methods Example (VB)

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