PDI supports joining of two tables form the same databse using a ‘Table Input’ method, performing the join in SQL only.
On the other hand, for joining two tables in different databases, users implement ‘Database Join’ step. However, in database join, each input row query executes on the target system from the main stream, resulting in lower performance as the number of queries implement on the B increases.
To avoid the above situation, there is yet another option to join rows form two different Table Input steps. You can use ‘Merge Join ‘step, using the SQL query having ‘ORDER BY’ clause. Remember, the rows must be perfectly sorted before implementing merge join.
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