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Tag: sql

Get movies that have categories

I have associative table movies and their categories. How can i get movies that have category 1 and 2? Result: Answer Do GROUP BY. Use HAVING with COUNT DISTINCT to make sure both 1 and 2 are there. Just for fun, you can also do a self join: Or, use INTERSECT:

SQL to append records

I have two tables tbl1 and tbl2. Consider tbl2 as the main set and tbl1 has been derived from other sources but will essentially now be a subset of tbl2. tbl1 cd productcd type 1 1 A 1 2 AB 1 3 A 2 3 AB 2 4 AC 3 1 A tbl2 cd productcd type priority 1 1 A

I wanna create a new table from the data of two tables

I have a A table to store the product name, the quantity and input day of goods in stock. In adverse conditions, invoices for the above products will be sent later. I will put the product name and invoice quantity in B table. The problem here is that I want to check the quantity of goods with invoice and with…

How to use data from multiple similar columns as rows in SQL

I have a table as below: ItemName 1mth_presale_cost 2mth_presale_cost 1mth_postsale_cost 2mth_postsale_cost 1000 10.1 12.1 12.5 15.1 1001 20.2 15.2 25.2 17.3 I want the result to be like below table: ItemName 1mth_cost 2mth_cost 1000 10.1 12.1 1000 12.5 15.1 1001 20.2 15.2 1001 25.2 17.3 I don’t want to…

MariaDB Created view takes too long

I have a problem. I have a table with 6 million records in it. Every record has a column dateTime, and for my code I need the most recent 16 records in ascending order. This took too long to query directly out of the original table, so I created a view using the following query: This means that the view

SQL MAX(col1, col2) with priorities

I need to select row with MAX(val1) for each group. If there is more than one row with equal val1 = MAX(val1) I need to select from them row with MAX(val2), etc. In pseudo code it should be like this: For example: I have table nums with one TEXT column name and three INTEGER columns — id, num1 and num2

Calculate total units sold and total sales value

Can you help me check my answers whether is this the right way? Im really new to database This is the question This is my answer The reason i use with read only constraint was to enhance the security! Answer The way I see it, query would look like this: If compared to yours: don’t select columns you don…