Skip to content

Tag: sql

SQL: Filling in Missing Records with Conditional

I need to count the number of products that existed in inventory by date. In the database however, a product is only recorded when it was viewed by a consumer. For example consider this basic table structure: Using the following query, I attempt to determine the amount of products in inventory on a given date…

Select rows which have a field in common with another row

I have two tables: products and postings. A product is a consumer product (ex. iPhone X), and a posting is a listing for a product on an online marketplace (ex. eBay posting). A single product has zero or more associated postings. Is there any way to select only postings which have a “sibling”? ie…

How do i write this without using ALL?

Write a query to find only those customers whose grade are, higher than every customer to the city New York Answer You can use MAX in your subquery instead: As @GordonLinoff points out, if there are no customers from New York, this query will fail. You can work around that by using COALESCE to convert the MAX…