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SQL: Optimize query with multiple CASE statements

I have a query with many CASE statements that runs for a very long time due to the number of rows. In my research I have not found a solution yet. Is there a way to write the CASE statements more efficiently and with better performance? database: Oracle table_a table table_y are all the same table where I SEL…

calculation with undefined number of rows

I would like to add a calculation taking into account we could have one, two, three or a lot of more rows. We can get all the data using the relations but I am a bit stuck because the number of relation are undefined. For example, as a source: Source Table id amount debt relation rn 123 250 225 NULL

User Defined Column name in select statement in Hivesql

I need to create user defined column name like below Postgresql query into HiveSql. Could you please help me on this. Answer Use backticks: But it is not possible to preserve case due to Hive limitation. Resulted column name will be in lower case: total customers See this answer: https://stackoverflow.com/a/5…

Database search results with context

I’ve built a system for archiving, aggregating, and indexing my IM history across different platforms (e.g. MSN Messenger, Hangouts, WhatsApp). The data is currently stored in an SQLite3 database, and relevant parts of the schema look something like this: There are also NOT NULL constraints on all colum…

Select everyone with the same ips

There is a table of users users: ETC… It is necessary to select all users with 1 ip. I tried to do it, it doesn’t work, not what I need to choose. Answer For MySQL 5.x use