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 HubDB Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"INSERT INTO NorthwindProducts (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 HubDB Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"UPDATE NorthwindProducts SET Name='Jon Doe' WHERE Industry='Floppy Disks')", 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 HubDB Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"DELETE FROM NorthwindProducts WHERE Id='1')", SQL_NTS);
SQLINTEGER rowCount = 0;
SQLRowCount(hstmt, &rowCount);