![]() A table can be also stored in multiple partitions, in which each group of rows will be stored in a specific partition, in one or more filegroups, based on a specific column. Table pages are stored by default in a single partition that resides in the PRIMARY default filegroup. Physically, SQL Server tables are stored in ta database as a set of 8 KB pages. Partitioned Tables are tables in which the data will be divided horizontally into separate unites in the same filegroup or different filegroups, based on a specific key, to enhance the data retrieval performance. System Tables are a special type of table in which the SQL Server Engine stores information about the SQL Server instance configurations and objects information, that can be queried using the system views. There are two types of temporary tables: a local temporary table that has the single number sign prefix (#) and can be accessed by the current connection only, and the Global temporary table that has two number signs prefix (#) and can be accessed by any connection once created.Ī Wide Table is a table the uses the Sparse Column to for optimized storage for the NULL values, reducing the space consumed by the table and increasing the number of columns allowed in that table to 30K columns. The first type is the Temporary Table that is stored in the tempdb system database. In addition to the basic user defined table, SQL Server provides us with the ability to work with other special types of tables. Proper table design, will make it easier and faster to store data into and retrieve data from the table. When you design a database table, the properties that are assigned to the table and the columns within the table will control the allowed data types and data ranges that the table accepts. You can create up to 2,147,483,647 tables in a database, with up to 1024 columns in each table. You can imagine the schema as a folder that contains a list of files. The schema also works as a security boundary, where you can limit database user permissions to be on a specific schema level only. SQL Server tables are contained within database object containers that are called Schemas. ![]() Tables can be also used as a security boundary/mechanism, where database users can be granted permissions at the table level. The table rows have no predefined order, so that, to display the data in a specific order, you would need to specify the order that the rows will be returned in. For example, the customers table contains one row for each customer, and each customer is described by the table columns that hold the customer information, such as the CustomerName and CustomerAddress. Each row is considered as an entity that is described by the columns that hold the attributes of the entity. The tables are the database objects that behave as containers for the data, in which the data will be logically organized in rows and columns format. Microsoft SQL Server is a relational database management systems (RDBMS) that, at its fundamental level, stores the data in tables. ![]()
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