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Tag: having-clause

SQL Select from many-to-one

I have two tables containing a one-to-many relationship. How should I select the “one” side given information for the “many” side? I’m using SQLite. Let’s say our first table, T1, is about cars and the second table, T2, is about the imperfections in each car. Let’s say we can describe the imperfections with an integer. So we have: We have

MySQL: Why are these two wrong? (Invalid use of group function, selected nothing after using having())

Credit:Leetcode_1076.Project Employees II Here is the sample table Project table: (project_id, employee_id) is the primary key of this table. I have tried several methods and managed to find the right one by using dense_rank(); however, I still don’t understand why these two syntaxes are wrong to select project_id with the largest number of employees: 1.Return null: {“headers”: [“project_id”, “n”], “values”:

behavior of DBMS after executing where clause

in a select query when some records doesn’t satisfy the condition in where clause, they will be omitted for executing subsequent clauses or not? for example consider we have a group by clause and after that, we have a condition in having clause on max(someThing). if a record has the maximum value of property someThing and it didn’t satisfy the