This is the fourteenth part of the SQLxD series. For your convenience you can find other parts in the table of contents in Part 1 – XML Transformation Today we implement grouping. Since we can group in multiple ways, we need to have grouping sets: Grouping set is just a set of columns which we … Continue reading SQLxD Part 14 — Grouping

This is the thirtieth part of the SQLxD series. For your convenience you can find other parts in the table of contents in Part 1 – XML Transformation We mentioned the natural join a few times and it finally the part when we implement it. Here we go: First, we compare guid collection lengths. This … Continue reading SQLxD Part 13 — Natural join

This is the twelfth part of the SQLxD series. For your convenience you can find other parts in the table of contents in Part 1 – XML Transformation Let’s implement tests for joins: They are rather straightforward. Next time we are going to implement natural join.

This is the eleventh part of the SQLxD series. For your convenience you can find other parts in the table of contents in Part 1 – XML Transformation Today we implement various JOIN operators. Let’s start with interfaces: Let’s start with the simplest join — CROSS JOIN: We simply implement nested loop algorithm and add … Continue reading SQLxD Part 11 — JOINs

This is the tenth part of the SQLxD series. For your convenience you can find other parts in the table of contents in Part 1 – XML Transformation Today we are going to test our code. First, we need to have some mocks: We start with tests for WHERE clause: And now tests for simple … Continue reading SQLxD Part 10 — WHERE and tests