The relational engine and the storage engine are the two major components of SQL Server.

-a select query from the client to the SQL Server, the first place to arrive is the SQL Server network interface, which is a network connection between the client and the Server protocol layer (SNI), contains a series of connection to the database engine and SQL Server Native Client (SNAC) APIs. SNI replaces the existing network libraries and MDAC (Microsoft Data Access components) in SQL Server 2000, which needs to be configured on both the client and the server. As mentioned in section 3.1, SQL Server has a total of 4 protocols, which are described in two of the most common.

1) TC P/IP: The most widely used protocol through which a specific IP address and port can be used to connect to SQL Server. The port number for SQL Server is 1433 by default, and the SQL Browser service uses UDP port 1434来 to find a named instance.

2) Named Pipes: Named Pipes, a protocol developed for LAN access, is not as fast as TCP/IP in the WAN. Configuring the Named Pipes service requires that you start SQL Server Configuration Manager, and then create a SQL Server alias that is used to name the pipe protocol. Named pipes are accessed using TCP port 445来, so the use of such a protocol requires ensuring the connectivity of this port, especially in the firewall configuration. As the entire SQL Server interacts with the outside world, regardless of which network connection protocol is used, SNI creates a secure TDS endpoint to the server for receiving and sending data, once the connection is established.

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The data cache is usually the largest portion of the buffer pool, so it is also the most consumed part of memory. You can use the sys.dm_os_buffer_descriptors DMV to check how much data cache is currently consumed by each database, with the following code:

SELECT COUNT (*) * 8/: 1024x768 as ' Cached Size (MB) Case database ID when 32767 then ' Resourcedb ELSE db_name (database one ID)

END as ' Database ' from Sys.dm_os_buffer_descriptors GROUP by Db_name (database_id), database_id ORDER by i Cached Size (MB) * DESC

The relational engine and the storage engine are the two major components of SQL Server.