When you finish using the connection, call the Close member function and destroy the CDatabase object. When you then construct CRecordset objects for operating on the connected data source, pass the recordset constructor a pointer to your CDatabase object. To use CDatabase, construct a CDatabase object and call its OpenEx member function. For more information, see the article Overview: Database Programming. If you are working with the Data Access Objects (DAO) classes rather than the Open Database Connectivity (ODBC) classes, use class CDaoDatabase instead. You can have one or more CDatabase objects active at a time in your application. Examples include Microsoft SQL Server, Microsoft Access, Borland dBASE, and xBASE. Type HDBC.Ī data source is a specific instance of data hosted by some database management system (DBMS). Open Database Connectivity (ODBC) connection handle to a data source. Affects all subsequent recordset Open, AddNew, Edit, and Delete calls. Sets the number of seconds after which database query operations will time out. Sets the number of seconds after which a data source connection attempt will time out. The data source returns to its previous state, as defined at the BeginTrans call, unaltered. Reverses changes made during the current transaction. You can establish these options ahead of time by calling SetQueryTimeout.Įstablishes a connection to a data source (through an ODBC driver). The default implementation sets the query timeout value. Returns nonzero if the CDatabase object is currently connected to a data source.Ĭalled by the framework to set standard connection options. Returns the name of the database currently in use. Identifies the effect of rolling back a transaction on an open recordset object. Identifies the effect of committing a transaction on an open recordset object. Returns the ODBC connection string used to connect the CDatabase object to a data source. Identifies the operations through which bookmarks persist on recordset objects. Commands in the transaction that alter the data source are carried out.Įxecutes a SQL statement. Returns nonzero if the CDatabase object is updatable (not read-only).Ĭompletes a transaction begun by BeginTrans. Returns nonzero if the data source supports transactions. The data source must support transactions for BeginTrans to have any effect.Īllows you to bind parameters before calling CDatabase::ExecuteSQL.Ĭancels an asynchronous operation or a process from a second thread.
Idatabase base clas undefined update#
Starts a "transaction" - a series of reversible calls to the AddNew, Edit, Delete, and Update member functions of class CRecordset - on the connected data source. You must initialize the object by calling OpenEx or Open. Syntax class CDatabase : public CObjectĬonstructs a CDatabase object. Represents a connection to a data source, through which you can operate on the data source.
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