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Tag: sql

LEFT JOIN WHERE not returning results

There are two tables with columns and I’m doing a basic LEFT JOIN: Case 1 Result: All good! Case 2, applied on same records Result: I was expecting to return doe’s records but it returned nothing. What am I missing? Answer Ah, the wonderful world of NULL handling. The problem arises when doing a c…

SQL – Get multiple values when limit 1

If I have a table like this: And use this query: SELECT ident,COUNT(*) FROM sales WHERE status=? AND team=? AND DATE(date) = DATE(NOW() – INTERVAL 1 DAY) GROUP BY ident order by COUNT(*) DESC LIMIT 1 I get the value: cucu1, since that has the most rows. But if my table is like this: It should return bot…

Replace values based on JOIN

Let’s say I have two data sets A and B After left join I should get FALSE value for Y in table A as it doesn’t have it in table B Answer Using your approach, if you intend to get a value of FALSE if the value doesn’t exist you can check for NULL in the name. The example below

Difference between JOIN and Inner JOIN in Sybase

I have a query like below. I don’t understand the difference between join vs inner join used on the below code. Aren’t they the same? This is written for Sybase. Please help me know the difference. Answer According to the standard INNER JOIN=JOIN. I think, Sybase does not break this rule

Deduce End date from a list of StartDate

I have the following data table And I would like to add another column corresponding to the EndDate, with the EndDate of one ID being the StartDate of the next. So it means the following result: Activity ID StartDate EndDate A 1 10/02/2021 11/02/2021 A 2 11/02/2021 12/02/2021 A 3 12/02/2021 ?? B 1 08/02/2021 …