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 Cassandra Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"INSERT INTO \"CData\".\"Sample\".Products (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 Cassandra Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"UPDATE \"CData\".\"Sample\".Products 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 Cassandra Source;", SQL_NTS, 0, 0, 0, 0);
SQLExecDirect(hstmt, (SQLCHAR*)"DELETE FROM \"CData\".\"Sample\".Products WHERE Id='1')", SQL_NTS);
SQLINTEGER rowCount = 0;
SQLRowCount(hstmt, &rowCount);