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• Cursor CLOSE fails, but the exception is not handled, and the cursor is reused with the same name without knowing that the cursor CLOSE failed.

• This is for HDB 5 or later version. In HDB 4 version, there is no error in this case.

• Example code

  Code Block
  language cpp
  declare cursor A; if ( sqlca.sqlcode != SQL_SUCCESS ) { exception handling; } open cursor A; if ( sqlca.sqlcode != SQL_SUCCESS ) { exception handling; } fetch cursor A; // fetch completed! if ( sqlca.sqlcode != SQL_SUCCESS ) { exception handling; } close cursor A; // No exception handling. /* close cursor A failed!! */ declare cursor A; if ( sqlca.sqlcode != SQL_SUCCESS ) { exception handling; }

• If this is the case, add exception handling to the cursor CLOSE statement and figure out what caused the cursor CLOSE to fail.

3. When the cursor is reused while the result of the data to be fetched remains

• If there is data to be fetched in the DB server, the result is deleted when the cursor is closed.

• In other words, the cursor with the same name cannot be reused until the data to be fetched is deleted. In order to reuse, the cursor must be FETCHed after OPENed.

  Code Block
  title Example 1 language cpp
  while(1) { fetch cursor A // Data to be fetched remains open cursor A // An error occurs when the cursor with the same name is reused while the data to be fetched remains! }

  Code Block
  while(1) { SQLFetch(stmt) // Data to be fetched remains SQLExecute(stmt) // An error occurs when the cursor with the same name is reused while the data to be fetched remains! }

• If this is the case, try to reuse the cursor after adding the cursor CLOSE statement.