topic Re: row1.Tag29 == null ? null :row1.Tag29 expression in tMap in Talend Studio

row1.Tag29 == null ? null :row1.Tag29 expression in tMap

jbhatt1810 — Sat, 16 Nov 2024 01:44:30 GMT

I have Row1 as my main and row2 as my look up table. In tMAP, I am trying to join column "Tag29". I am using below expression for same. Basically what I am trying to achieve is, if row1.Tag29 is null then dont join row1 Tag29 with row2Tag29 and if its not null then join row1.Tag29. For some reason, I think the expression is resolved as null string and it tries mapping "null" with row2.Tag29. shouldn't it be empty if row1.Tag29 value is null?

row1.Tag29 == null ? null : row1.Tag29

Re: row1.Tag29 == null ? null :row1.Tag29 expression in tMap

Anonymous — Wed, 05 Aug 2020 00:17:28 GMT

is row1.Tag29 a join key? Can you share a screenshot of tMap?

Regards

Shong

Re: row1.Tag29 == null ? null :row1.Tag29 expression in tMap

jbhatt1810 — Mon, 10 Aug 2020 21:22:24 GMT

@Shicong Hong See below screenshot: Yes row1 aka generatedFileData is the main. If generatedFileData.Tag29 is null then it should be empty in the expr.key part of lookup as shown in another screenshot. Instead it resolves it as "null" string value and hence it ends up joining "null" string with lookup.Tag29 column

Re: row1.Tag29 == null ? null :row1.Tag29 expression in tMap

Anonymous — Tue, 11 Aug 2020 03:01:26 GMT

As long as you set any expression there, it will consider this field as a join key regardless of what value it is.

If you don't want to do join if this field is null, you need to filter the data before join and do another join.