Difference between a formula and an SQL expression.
MJLEE
Registered Posts: 6 ✭✭✭✭
Hello, I have a question about difference between a formula and an SQL expression.
1. There are "a formula" and an "an SQL expression" options in a few recipe and processors. In case of "a formula", I think I need to refer to the link as follows "https://doc.dataiku.com/dss/latest/advanced/formula.html" offered by Dataiku, and in case of "an SQL expression", I may refer to here "http://www.h2database.com/html/functions.html#difference". Is my understanding right?
2. In terms of custom aggregations in GROUP recipe, is it only possible to use SQL?
1. There are "a formula" and an "an SQL expression" options in a few recipe and processors. In case of "a formula", I think I need to refer to the link as follows "https://doc.dataiku.com/dss/latest/advanced/formula.html" offered by Dataiku, and in case of "an SQL expression", I may refer to here "http://www.h2database.com/html/functions.html#difference". Is my understanding right?
2. In terms of custom aggregations in GROUP recipe, is it only possible to use SQL?
Best Answer
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For filters, the "SQL expression" depends on the kind of database you are using. It is only meaningful if the input is a SQL database (unfortunately, we always show the selector, even if it is meaningless)
For custom aggregations, they can indeed only be SQL (DSS formula only does line-per-line evaluation, not aggregation). The SQL dialect to use is either the one of your input database (if any), or H2 (if the input is not database nor HDFS)
