Scaling out queries using PolyBase requires using SQL Server Enterprise edition as a head node. Certain features including SQL Server Reporting Services, SQL Server Analysis Services, Machine Learning Services, PolyBase, and Stretch Database are not available in SQL Server on Linux. Interleaved Execution is available in all editions. Microsoft SQL Server Versions List. ★ What is the latest version of SQL Server? New ★ SQL Server Editions: Free, Paid, Specialized ← direct download links New Microsoft SQL Server With Power View For Multidimensional Models Customer Technology Preview 5/5(). Editions and supported features of SQL Server 03/28/; 18 minutes to read +16; In this article. APPLIES TO: SQL Server Azure SQL Database Azure Synapse Analytics (SQL DW) Parallel Data Warehouse This topic provides details of features supported by the various editions of SQL Server
It is similar to an enterprise edition for the non-production environment. It is mainly used for build, test, and demo. SQL Server Express: It is for small scale applications and free to use.
Ask your brain….!!! Finally, mom does some processing with Milk, coffee, sugar and prepare coffee to serve it hot. This component handle storage, Rapid transaction Processing, and Securing Data. SQL Server: Executable name is sqlservr. SQL Server Agent: It performs the role of Task Scheduler.
It can be triggered by any event or as per demand. Executable name is sqlagent. SQL Server Browser: This listens to the incoming request and connects to the desired SQL server instance. Executable name is sqlbrowser. Executable name is fdlauncher. This allows backup and restoration of data files when the SQL server is not running.
Executable name is sqlwriter. Provide Data analysis, Data mining and Machine Learning capabilities. SQL server is integrated with R and Python language for advanced analytics.
Executable name is msmdsrv. Provides reporting features and decision-making capabilities. It includes integration with Hadoop. Executable name is ReportingServicesService.
Provided Extract-Transform and Load capabilities of the different type of data from one source to another. It can be view as converting raw information into useful information. Executable name is MsDtsSrvr. These are divided into two: Specialized indexing methods were made available for XML data. When the data is accessed over web services, results are returned as XML.
SQL Server has also been enhanced with new indexing algorithms, syntax and better error recovery systems. Data pages are checksummed for better error resiliency, and optimistic concurrency support has been added for better performance. Permissions and access control have been made more granular and the query processor handles concurrent execution of queries in a more efficient way. Partitions on tables and indexes are supported natively, so scaling out a database onto a cluster is easier.
NET Framework. Automatic failover requires a witness partner and an operating mode of synchronous also known as high-safety or full safety. Prior to SP1, it was not enabled by default, and was not supported by Microsoft.
SQL Server also includes support for structured and semi-structured data, including digital media formats for pictures, audio, video and other multimedia data. In current versions, such multimedia data can be stored as BLOBs binary large objects , but they are generic bitstreams. Intrinsic awareness of multimedia data will allow specialized functions to be performed on them. Backing up and restoring the database backs up or restores the referenced files as well.
According to a Microsoft technical article, this simplifies management and improves performance. A "Round Earth" data type GEOGRAPHY uses an ellipsoidal model in which the Earth is defined as a single continuous entity which does not suffer from the singularities such as the international dateline, poles, or map projection zone "edges".
It also includes Resource Governor that allows reserving resources for certain users or workflows. It also includes capabilities for transparent encryption of data TDE as well as compression of backups. However, the x64 platform would continue on in force. It was released to manufacturing on March 6, Whilst small tables may be entirely resident in memory in all versions of SQL Server, they also may reside on disk, so work is involved in reserving RAM , writing evicted pages to disk, loading new pages from disk, locking the pages in RAM while they are being operated on, and many other tasks.
The RTM version is These editions are: It can manage databases as large as petabytes and address 12 terabytes of memory and supports logical processors CPU cores. It differs from Enterprise edition in that it supports fewer active instances number of nodes in a cluster and does not include some high-availability functions such as hot-add memory allowing memory to be added while the server is still running , and parallel indexes. It includes the Standard Edition capabilities and Business Intelligence tools: Note that this edition has been retired in SQL Server Two additional editions provide a superset of features not in the original Express Edition.
For example, it supports a subset of the standard data types, does not support stored procedures or Views or multiple-statement batches among other limitations. The 3. NET Synchronization Services. Starting early , Microsoft made this edition free of charge to the public. Evaluation SQL Server Evaluation Edition, also known as the Trial Edition, has all the features of the Enterprise Edition, but is limited to days, after which the tools will continue to run, but the server services will stop.
Intended for use as an application component, it did not include GUI management tools. Later, Microsoft also made available a web admin tool. Had workload or connection limits like MSDE, but no database size limit. Includes standard management tools. It supports logical processors and virtually unlimited memory and comes with StreamInsight Premium edition. TDS is an application layer protocol, used to transfer data between a database server and a client. Initially designed and developed by Sybase Inc.
Consequently, access to SQL Server is available over these protocols. SQL Server supports different data types, including primitive types such as Integer, Float, Decimal, Char including character strings , Varchar variable length character strings , binary for unstructured blobs of data , Text for textual data among others.
The rounding of floats to integers uses either Symmetric Arithmetic Rounding or Symmetric Round Down fix depending on arguments: In addition to tables, a database can also contain other objects including views , stored procedures , indexes and constraints , along with a transaction log. A SQL Server database can contain a maximum of objects, and can span multiple OS-level files with a maximum file size of bytes 1 exabyte.
Secondary data files, identified with a. Log files are identified with the. A page is marked with a byte header which stores metadata about the page including the page number, page type, free space on the page and the ID of the object that owns it. Page type defines the data contained in the page: A database object can either span all 8 pages in an extent "uniform extent" or share an extent with up to 7 more objects "mixed extent". The partition size is user defined; by default all rows are in a single partition.
A table is split into multiple partitions in order to spread a database over a computer cluster. Rows in each partition are stored in either B-tree or heap structure.
If the table has an associated, clustered index to allow fast retrieval of rows, the rows are stored in-order according to their index values, with a B-tree providing the index.
The data is in the leaf node of the leaves, and other nodes storing the index values for the leaf data reachable from the respective nodes. If the index is non-clustered, the rows are not sorted according to the index keys. An indexed view has the same storage structure as an indexed table. A table without a clustered index is stored in an unordered heap structure.
However, the table may have non-clustered indices to allow fast retrieval of rows. In some situations the heap structure has performance advantages over the clustered structure.
Both heaps and B-trees can span multiple allocation units. The amount of memory available to SQL Server decides how many pages will be cached in memory. The buffer cache is managed by the Buffer Manager. Either reading from or writing to any page copies it to the buffer cache. Subsequent reads or writes are redirected to the in-memory copy, rather than the on-disc version. The page is updated on the disc by the Buffer Manager only if the in-memory cache has not been referenced for some time.
Each page is written along with its checksum when it is written. When reading the page back, its checksum is computed again and matched with the stored version to ensure the page has not been damaged or tampered with in the meantime.
As such, it needs to control concurrent access to shared data, to ensure data integrity—when multiple clients update the same data, or clients attempt to read data that is in the process of being changed by another client. SQL Server provides two modes of concurrency control: When pessimistic concurrency control is being used, SQL Server controls concurrent access by using locks.
Locks can be either shared or exclusive. Exclusive lock grants the user exclusive access to the data—no other user can access the data as long as the lock is held. Shared locks are used when some data is being read—multiple users can read from data locked with a shared lock, but not acquire an exclusive lock.
The latter would have to wait for all shared locks to be released. Locks can be applied on different levels of granularity—on entire tables, pages, or even on a per-row basis on tables. For indexes, it can either be on the entire index or on index leaves. The level of granularity to be used is defined on a per-database basis by the database administrator.
While a fine-grained locking system allows more users to use the table or index simultaneously, it requires more resources, so it does not automatically yield higher performance.
SQL Server also includes two more lightweight mutual exclusion solutions—latches and spinlocks—which are less robust than locks but are less resource intensive. SQL Server also monitors all worker threads that acquire locks to ensure that they do not end up in deadlocks —in case they do, SQL Server takes remedial measures, which in many cases are to kill one of the threads entangled in a deadlock and roll back the transaction it started.
The Lock Manager maintains an in-memory table that manages the database objects and locks, if any, on them along with other metadata about the lock. Access to any shared object is mediated by the lock manager, which either grants access to the resource or blocks it. SQL Server also provides the optimistic concurrency control mechanism, which is similar to the multiversion concurrency control used in other databases.
The mechanism allows a new version of a row to be created whenever the row is updated, as opposed to overwriting the row, i. Both the old as well as the new versions of the row are stored and maintained, though the old versions are moved out of the database into a system database identified as Tempdb. When a row is in the process of being updated, any other requests are not blocked unlike locking but are executed on the older version of the row.
If the other request is an update statement, it will result in two different versions of the rows—both of them will be stored by the database, identified by their respective transaction IDs. The query declaratively specifies what is to be retrieved.
It is processed by the query processor, which figures out the sequence of steps that will be necessary to retrieve the requested data. The sequence of actions necessary to execute a query is called a query plan. There might be multiple ways to process the same query.
For example, for a query that contains a join statement and a select statement, executing join on both the tables and then executing select on the results would give the same result as selecting from each table and then executing the join, but result in different execution plans. In such case, SQL Server chooses the plan that is expected to yield the results in the shortest possible time. This is called query optimization and is performed by the query processor itself. Given a query, then the query optimizer looks at the database schema , the database statistics and the system load at that time.
It then decides which sequence to access the tables referred in the query, which sequence to execute the operations and what access method to be used to access the tables. For example, if the table has an associated index, whether the index should be used or not: Finally, it decides whether to execute the query concurrently or not.
While a concurrent execution is more costly in terms of total processor time, because the execution is actually split to different processors might mean it will execute faster. Once a query plan is generated for a query, it is temporarily cached. For further invocations of the same query, the cached plan is used. Unused plans are discarded after some time. Stored procedures are parameterized T-SQL queries, that are stored in the server itself and not issued by the client application as is the case with general queries.
Stored procedures can accept values sent by the client as input parameters, and send back results as output parameters. They can call defined functions, and other stored procedures, including the same stored procedure up to a set number of times. They can be selectively provided access to. Unlike other queries, stored procedures have an associated name, which is used at runtime to resolve into the actual queries.
Also because the code need not be sent from the client every time as it can be accessed by name , it reduces network traffic and somewhat improves performance. Main article: It exposes keywords for the operations that can be performed on SQL Server, including creating and altering database schemas, entering and editing data in the database as well as monitoring and managing the server itself.
Client applications that consume data or manage the server will leverage SQL Server functionality by sending T-SQL queries and statements which are then processed by the server and results or errors returned to the client application. For this it exposes read-only tables from which server statistics can be read. Management functionality is exposed via system-defined stored procedures which can be invoked from T-SQL queries to perform the management operation. Linked servers allow a single query to process operations performed on multiple servers.
It natively implements support for the SQL Server features including the Tabular Data Stream implementation, support for mirrored SQL Server databases, full support for all data types supported by SQL Server, asynchronous operations, query notifications, encryption support, as well as receiving multiple result sets in a single database session. NET Framework. Unlike most other applications that use.
NET Framework runtime , i. SQLOS provides deadlock detection and resolution services for.