Hello all,
I am looking for ideas on how to tackle a problem using knime.
I have a table containing many rows of data where any of the fields can be NULL. For example:
| NAME | AGE | Cubicle | COMMENT1 | COMMENT2 |
| John | 23 | rhinocerous | ||
| Alice | 37 | 1 | ||
| Tim | 56 | 2 | Banana |
I want to query an Oracle databse to see if each of these rows already exists in the database. For a row to exist, all fields must match. My initial thorugh was to use a "Table Row To Variable Loop Start" --> "Database Reader," however, the NULL/missing values don't work in this paradigm since:
- "Table Row To Variable Loop Start" doesn't allow NULL values to be passed
- The SQL query used in the database requires me to use for "IS NULL" instead of "=" when comparing NULL values.
The only other way I can think to do this is to use a separate SQL query, each in its own "Database Reader" node, to indiviaually handle the different cases of possible NULL values. This is a bit unweildy since it would require dozens of separate database reader nodes.
I'm sure there is something simpler that is escaping my mind, so all suggestions are welcome.
Thank you.