Tool in Mylly: Relation algebra / Join | fi
Join of relations
Join takes two relations and produces the set of combinations of their attributes where the shared attributes match.
The input and output relations are represented as TSV files.
Example
The first input relation consists of some word forms annotated with a lemma, a sentence number, and a token number. The second input relation consists of sentence numbers annotated with the mood of a sentence.
| sen | tok | lemma | word |
|---|---|---|---|
| 3 | 3 | niin | niin |
| 3 | 2 | se | se |
| 3 | 1 | olla | on |
| 5 | 1 | olla | on |
| sen | mood |
|---|---|
| 3 | calm |
| 4 | calm |
| 5 | angry |
The output relation consists of those word forms in the first input relation that had their sentence number in the second input relation (all of them), still annotated with their token and sentence numbers and lemmas, and now also with the mood of the sentence.
| tok | sen | mood | lemma | word |
|---|---|---|---|---|
| 3 | 3 | calm | niin | niin |
| 2 | 3 | calm | se | se |
| 1 | 3 | calm | olla | on |
| 1 | 5 | angry | olla | on |
Related tools
See also
- Relation algebra for context
