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Tag: select

Count occurrences in SQL

I have a table with the following data And I would like to have for each ID how many occurrences of each type there are Is there a way in SQL (something like a pivot table) Answer I would recommend conditional aggregation. This is a cross-database solution that is more flexible than vendor-specific solutions (and at least as efficient):

How do I do this without a subquery?

I need to make the same query, but without a subquery! I need to get the count of rows in which genre_id is equal to the :deletedGenreId and the org_type_id value of this line in this table is not unique Answer There is nothing wrong with sub-query. Sub-query actually can help boost performance and increase code readability if you do

Check if multiple records exist, with the same id

I am trying to check if multiple records exists with pageId IN(?,?,?) in the chatParticipants table. This is an example of the table structure: This is the SQL query I have tried: Expected behavior: If a conversation already exists, with the given (x) participants, that is, with the same chatId value, then it must return the chatId value. The above

MYSQL Specific Order With Conditionals

Okay… I have three columns that I’d like to order based on their conditions. Column 1 (INT) = last_reboot Column 2 (BOOL) = onlinecheck Column 3 (INT) = drive_use I’d like “last_reboot” to be default and ordered descending. If “onlinecheck” = 0, I’d like it to be at the top of my query else ordered by the the “last_reboot” desc.

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