Modifying Data
The following code examples show how to use data modification statements.
Procedure for Updates
Use SQLExecDirect to execute data manipulation statements and use the SQLRowCount function to obtain the affected rows.
INSERT
To insert updates:
SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);
SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, 0);
SQLAllocHandle(SQL_HANDLE_DBC, henv, &hdbc);
SQLDriverConnect(hdbc, 0, (SQLCHAR*)"Dsn=CData Access Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"INSERT INTO Orders (ShipCity) VALUES ('Raleigh')", SQL_NTS);
SQLINTEGER rowCount = 0;
SQLRowCount(hstmt, &rowCount);
UPDATE
To retrieve updates:
SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);
SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, 0);
SQLAllocHandle(SQL_HANDLE_DBC, henv, &hdbc);
SQLDriverConnect(hdbc, 0, (SQLCHAR*)"Dsn=CData Access Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"UPDATE Orders SET ShipCity='Raleigh' WHERE ShipCountry='USA')", SQL_NTS);
SQLINTEGER rowCount = 0;
SQLRowCount(hstmt, &rowCount);
DELETE
To delete updates:
SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);
SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, 0);
SQLAllocHandle(SQL_HANDLE_DBC, henv, &hdbc);
SQLDriverConnect(hdbc, 0, (SQLCHAR*)"Dsn=CData Access Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"DELETE FROM Orders WHERE Id='10261')", SQL_NTS);
SQLINTEGER rowCount = 0;
SQLRowCount(hstmt, &rowCount);