topic Re: Select the first rows for SQL Query in App Development

Select the first rows for SQL Query

pietapa — Tue, 02 May 2023 09:31:30 GMT

Hello guys,
I have a large list of containers that I need to use for my SQL query. However, I keep encountering an error when I try to run the SQL query with the entire list. The error message usually states that a column cannot be found or there are issues with the connection.

To work around this problem, I am looking to retrieve a subset of the containers and use that for my SQL query instead. Specifically, I would like to retrieve the first five or more rows of containers and store them in an array.

However, I am unsure of how to retrieve a subset of rows from the container list. Could you please provide guidance on how I can achieve this?

Re: Select the first rows for SQL Query

Kushal_Chawda — Tue, 02 May 2023 11:23:55 GMT

@pietapa assuming you have container list stored somewhere which you can use. I have used first 5 in load to load first 5 values.

containers: LOAD concat(chr(39) & container & chr(39) ,',') as list_container; first 5 LOAD distinct container FROM Source; let vContainerList = peek('list_container',0,'containers'); drop table containers; then, you can pass the list to SQL query like below query: SQL select * FROM TableName where container in ('$(vContainerList)');

Re: Select the first rows for SQL Query

pietapa — Tue, 02 May 2023 11:12:48 GMT

Unfortunately, I tried your solution but it does not work...

VContainerList is still empty...

Re: Select the first rows for SQL Query

Kushal_Chawda — Tue, 02 May 2023 11:25:04 GMT

@pietapa Not sure how you are doing it but if you follow same steps it should not generate NULL