I need to come up with a query that can do the following: I have a table with a bunch of transaction records, whose attributes are not important, other than the attribute Date. I need to come up ...
I have a tree structure of light bulbs. I want to turn on all the light bulbs starting from the leafs of the tree. A light bulb cannot be turned on unless all its immediate children are turned on. ...
At the moment I have a table setup that looks somewhat like this: create table tbl_locationcollections ( id int(11) PRIMARY KEY IDENTITY, --(Primary Key), name varchar(100) not null, ...
Background Most modern databases have XML functions that can be used to extract data in an XML format. I want to avoid the task of manually calling XML functions to extract the data. This problem ...
I have one question that confusing me. By logical query processing, the SELECT clause comes before the ORDER BY clause, and in theory, every step in a query creates a virtual table. So, how is it ...
The ANSI SQL standard defines (chapter 6.5, set function specification) the following behaviour for aggregate functions on empty result sets: COUNT(...) = 0 AVG(...) = NULL MIN(...) = NULL MAX(...) = ...