Stairway to T-SQL DML

Stairway to T-SQL DML Level 4: The Mathematics of SQL: Part 1

A relational database contains tables that relate to each other by key values. When querying data from these related tables you may choose to select data from a single table or many tables. If you select data from many tables, you normally join those tables together using specified join criteria. The concepts of selecting data from tables and joining tables together is all about managing and manipulating sets of data. In Level 4 of this Stairway we will explore the concepts of set theory and mathematical operators to join, merge, and return data from multiple SQL Server tables.

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Introduction to the Cosmos DB Emulator

Cosmos DB delivers a wide range of advantages over traditional SQL and NoSQL-based data stores, including support for multiple consistency levels, latency and throughput guarantees, policy-based geo-fencing, automatic scaling, and multi-master replication model. However, it is a significant departure from the traditional database management and development approach that most database administrators are familiar with. Discover the offerings that you can use at no cost to gain hands-on experience with Cosmos DB.

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Question of the Day

Creating a JSON Document III

I have this data in a table called dbo.NFLTeams

TeamID  TeamName       City             YearEstablished
------  --------       ----             ---------------
1       Cowboys        Dallas           1960
2       Eagles         Philadelphia     1933
3       Packers        Green Bay        1919
4       Chiefs         Kansas City      1960
5       49ers          San Francisco    1946
6       Broncos        Denver           1960
7       Seahawks       Seattle          1976
8       Patriots       New England      1960
If I run this code, how many rows are returned?
SELECT TOP 2 
  json_objectagg('Team' : TeamName)
FROM dbo.NFLTeams;

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