transformations:merge
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| Both sides previous revisionPrevious revision | Next revisionBoth sides next revision | ||
| transformations:merge [2017/01/01 15:32] – dmitry | transformations:merge [2017/05/01 22:53] – dmitry | ||
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| This transformation appends one or more columns from another table where certain columns in both tables match. | This transformation appends one or more columns from another table where certain columns in both tables match. | ||
| - | There are two possible merge modes: | + | There are three possible merge modes: |
| * Lookup Mode -- get **first** matching combination from the other table. If there are other combinations they are ignored. | * Lookup Mode -- get **first** matching combination from the other table. If there are other combinations they are ignored. | ||
| * Left Join Mode -- get **all** matching combinations from the other table. It can increase number or rows in the current table. | * Left Join Mode -- get **all** matching combinations from the other table. It can increase number or rows in the current table. | ||
| - | + | * Full Join Mode -- include all combinations of keys from both tables. Equivalent to the full outer join in SQL. | |
| - | To make full outer join, first, append rows that exist in the other table but are missing in the current table using [[transformations: | + | |
| EXAMPLE | EXAMPLE | ||
transformations/merge.txt · Last modified: 2024/04/11 23:55 by craigt