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 CDS Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"INSERT INTO Accounts (Name) VALUES ('Jon Doe')", 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 CDS Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"UPDATE Accounts SET Name='Jon Doe' WHERE Name='MyAccount')", 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 CDS Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"DELETE FROM Accounts WHERE AccountId=''00000000-0000-0000-0000-000000000000'')", SQL_NTS);
SQLINTEGER rowCount = 0;
SQLRowCount(hstmt, &rowCount);