TDAODatabase provides control over a connection to single database in a database application.
Use TDAODatabase when a database application requires any of the following control over a database connection:
procedure BeginTrans;
Opens new transaction.
procedure Close;
Closes a dataset.
Call Close to set the Active property of a dataset to False.
When Active is False, the dataset is closed; the dataset cannot read data from or write data to the database.
procedure CommitTrans;
CommitTrans finishes current transaction and keeps changes.
procedure Execute(SQL: string);
Executes the SQL statement.
Call Execute to execute the INSERT, UPDATE, or DELETE statement without parameters.
procedure GetQueryDefNames(List: TStrings);
Populates a string list with the names of QueryDefs associated with a specified database.
procedure GetTableIndexes(TableName: string; List: TStrings);
Populates a string list with the names of Indexes associated with a specified table.
procedure GetTableNames(List: TStrings);
Populates a string list with the names of TableDefs associated with a specified database.
procedure Open;
Connects to a database.
Call Open to establish a connection to a database, specified by the DatabaseName property.
Setting Connected to True also connects to the database.
procedure Rollback;
Cancels all changes for the current transaction and ends the transaction.
property Connected : Boolean
Indicates whether or not a database connection is active.
Set Connected to True to establish a database connection without opening a dataset.
Set Connected to False to close a database connection. An application can check Connected to determine
the current status of a database connection.
property CreateWorkspace : Boolean
Set CreateWorkspace to True when you need to create Workspace object.
Workspace is necessary for work with Access user security.
property DatabaseName : string
Expression specifying a name of an existing file of a database.
property Exclusive : Boolean
Defines a type of access to a database.
Set Exclusive to True to define an exclusive access to a database.
Set Exclusive to False for common access.
property Password : string
Use Password to specify password of the protected database.
Note
It is the password of a database, instead of user.
property ReadOnly : Boolean
Set ReadOnly to True if the database opens only for reading.
property Workspace : TWorkspace
Workspace provides properties, which are necessary for work with secured databases.
property Datasets : TList
Provides an indexed array of all active datasets for a database component.
Use DataSets to access active datasets associated with a database component.
An active dataset is one that is currently open.
property RecordsAffected : Integer
Returns number of records, which were used by last call of a method Execute.
The returned value lays in an interval from 0 up to number of records, which were used
by last call of method Execute for TDAODatabase.
_Database : Database;
Provides interface to native DAO Database object.
_Workspace : Workspace;
Provides interface to native DAO Workspace object.
Note
You may use interface to Workspace only when CreateWorkspace is True.