We look at the history of Windows Read more. Website Shortcut on Your Desktop reviewed by Web Webster This Webopedia guide will show you how to create a website shortcut on your desktop using What are the Five Generations of Computers? Reviewed by Web Webster Learn about each of the 5 generations of computers and major technology developments that have led to the computing devices that Launched in , Hotmail was one of the first public webmail services that could be accessed from any web browser.
At its peak in Related Articles. Lucas Ledbetter - January 12, 0. Reference The Complete List of From A3 to ZZZ we list Vangie Beal - January 10, 0. Lucas Ledbetter - January 10, 0. Advertise with Us. Our Brands. Each of these tables would have different fields that are relevant to the information stored in the table.
Nearly all e-commerce sites uses databases to store product inventory and customer information. By storing website data in a database, the data can be easily searched, sorted, and updated. This flexibility is important for e-commerce sites and other types of dynamic websites. Early databases were relatively "flat," which means they were limited to simple rows and columns, like a spreadsheet. See also " flat file database ".
However, today's relational databases allow users to access, update, and search information based on the relationship of data stored in different tables. Relational databases can also run queries that involve multiple databases. While early databases could only store text or numeric data, modern databases also let users store other data types such as sound clips, pictures, and videos.
Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services. Privacy policy. Applies to: SQL Server all supported versions. At a minimum, every SQL Server database has two operating system files: a data file and a log file.
Data files contain data and objects such as tables, indexes, stored procedures, and views. Log files contain the information that is required to recover all transactions in the database. Data files can be grouped together in filegroups for allocation and administration purposes. For example, a simple database named Sales has one primary file that contains all data and objects and a log file that contains the transaction log information.
A more complex database named Orders can be created that includes one primary file and five secondary files. The data and objects within the database spread across all six files, and the four log files contain the transaction log information.
By default, the data and transaction logs are put on the same drive and path to handle single-disk systems. This choice may not be optimal for production environments. We recommend that you put data and log files on separate disks. The logical file name must comply with the rules for SQL Server identifiers and must be unique among logical file names in the database. It must follow the rules for the operating system file names.
Only read-only databases and read-only secondary filegroups are allowed to be put on an NTFS compressed file system. For space savings, it is highly recommended to use data compression instead of file system compression. When multiple instances of SQL Server are running on a single computer, each instance receives a different default directory to hold the files for the databases created in the instance.
Pages in a SQL Server data file are numbered sequentially, starting with zero 0 for the first page in the file. Each file in a database has a unique file ID number.
To uniquely identify a page in a database, both the file ID and the page number are required. The following example shows the page numbers in a database that has a 4-MB primary data file and a 1-MB secondary data file. A file header page is the first page that contains information about the attributes of the file. Several of the other pages at the start of the file also contain system information, such as allocation maps.
One of the system pages stored in both the primary data file and the first log file is a database boot page that contains information about the attributes of the database. SQL Server files can grow automatically from their originally specified size. When you define a file, you can specify a specific growth increment.
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