Microsoft SQL Server | Meaning, Uses & Products Indexes in SQL What is a Primary Key in SQL? What is a Foreign Key in SQL? Next Lesson SQL Index Types: Clustered & Nonclustered Index Fragmentation in SQL SQL Normalization: Example & Rules SQL Collation: SQL Server & MySQL Wha...
When you have a many-to-many relation, you almost always have a junction table with a two-column primary key and foreign-key relations to the other two tables.
The primary key in the Customers table is CustomerNo, and the primary key in the Orders table is OrderNo. The primary key uniquely identifies the table and contains the value that the foreign key refers to. Primary keys must be unique to each row of data. In the Orders table, the Custo...
Foreign Keys A foreign key is a set of one or more columns in a table that refers to the primary key in another table. There aren’t any special code, configurations, or table definitions you need to place to officially “designate” a foreign key. In the diagram below look at the Sal...
The key is never passed to SQL Server. Dynamic Data Masking: If specified in the table definition, masked data is hidden from most users, and only users with UNMASK permission can see the complete data. Row Level Security: Data access can be restricted at the database engine level, so ...
SQL Server 2019 Analysis Services GA (Generally Available) Tabular model compatibility level This release introduces the 1500 compatibility level for tabular models. Query interleaving Query interleaving is a tabular mode system configuration that can improve user query response times in high-concurren...
SQL Server 2019 Analysis Services GA (Generally Available) Tabular model compatibility level This release introduces the 1500 compatibility level for tabular models. Query interleaving Query interleaving is a tabular mode system configuration that can improve user query response times in high-concurrency sc...
The two approximate numeric data types in SQL Server are float and real. The syntax for the SQL Server float data type is FLOAT [(n)] where n is the number of bits used to store the mantissa of the number in scientific notation. It dictates the precision and storage size. While the ...
what I’ve learned about a subset of NoSQL databases called “document databases.” Another subset is key-value pair databases. Azure Table Storage, which I wrote about in my July 2010 Data Points column (msdn.microsoft.com/magazine/ff796231), is an example of a key-value pair NoSQL ...
Another subset is key-value pair databases. Azure Table Storage, which I wrote about in my July 2010 Data Points column (msdn.microsoft.com/magazine/ff796231), is an example of a key-value pair NoSQL store. I should first address the definition of NoSQL. It’s become a bit of a ...