sql server dba introduction

1. Introduction to the problem:In general, when using a program to connect to a database, when the database server does not exist, or the database server does not start,Causes the database connection to fail, which can take a long time. Therefore, before connecting, it is necessary to make a judgment on these, and then return to the User AThe correct message to r

Server| Program | Advanced Introduction: SQL is a structured query language for relational databases. It is divided into many species, but most are loosely rooted in the latest standard SQL-92 of the national standardization Organization. A typical execution statement is query, which collects records that are more comp

is an abbreviation for Internet Information Services The Internet Information Service This tool enables you to define registered virtual directories and create associations between virtual directories and SQL Server instances on the computer running IIS 1.3.10 DTC Client Support DTC distribute Transaction Coordinator distributed Transaction Coordinator for providing and managing distributed transactions

DiagramDesign principles of 10.1.3 e-r diagram10.2 Database Diagram Designer10.3 Database Diagram10.3.1 Creating a Database diagram10.3.2 Saving a database diagram10.3.3 Open a database diagram10.3.4 Renaming a database diagram10.3.5 Deleting a database diagram10.4 Common face questions10.5 Summary10.6 Exercises 　　 The 3rd chapter of Transact-SQL Common grammar and Real pour11th Chapter Transact-SQL statem

smooth sailing. When the site's users started to grow at a high speed on a daily basis, the problem immediately occurred. The customer sent an email complaining that the website performance was too slow and that the website was losing customers. You started to investigate the system and soon found that the system was very slow when accessing or updating data. When I started the database, the database records increased rapidly, and some table records reached thousands of rows. The test team cond

Custom report PERFORMANCE_DASHBOARD_MAIN.RDL, load and see the Performance Analysis report:Performance dashboard does not collect or store any information, but instead extracts the current data from within SQL Server. Because of this, a lot of data starts at a certain time, but sometimes you see some historical data as a byproduct to see how SQL

Label:SQL Injection About the harm of SQL injection here is not much to do introduction, I believe we also know the strong relationship among them. Here are some SQL injection events that everyone interested can look at There are several ways to prevent SQL injection: 1. Using type-safe

, Windows version, patch to check, Although it is not exactly specified that the OS must be exactly the same, the consistent version is less unusual.Recovery model, compatibility level for SQL Server databases:Check the recovery model and compatibility level, which can be implemented using the following statement: Use master go SELECT name [database name], recovery_model_desc [recovery mode], case

After sqlserver2005, MSSQL began to use the recursive query method. Compare the methods for writing stored procedures or functions at the beginning. This method is simpler and more flexible. Oracle also has its own tree structure recursive query method, connect Next I will write a piece of SQL code by myself, and briefly comment out some usage of the CTE shared expression. Query the root node and subnode of the tree structure. Code --

limited, too many useless execution plans will be occupied, which will reduce the available memory of SQL Server, in this way, more memory pages are exchanged with the disk when the query is executed, especially when the query is large. If the maximum available memory is not limited, the SQL server will occupy more me

Tags: multiple table address comment Sele libffi cal download field clientSqladvisor is an open source SQL Index optimization recommendation tool by the company's technical engineering Department DBA Team (Beijing) to develop and maintain an analytic SQL tool for index optimization recommendations. Based on the original ecological lexical analysis of MySQL, this

Label:Write in front: This is the first T-SQL query Advanced series article. But the T-SQL query step-up series is far from finished. This topic is advanced and I think it is because this topic requires some advanced knowledge as the basis. If there is any mistake in the article, please do not hesitate to correct me. The content of this article needs to be indexed knowledge as the basis.

, which means that SQL Server must determine for each row whether it satisfies all the conditions in the WHERE clause. So an index is useless for an expression that does not satisfy the Sarg form.after the introduction After Sarg, let's summarize the experience of using SARG and some of the findings that have been encountered in practice and in some materials:1.

1. Introduction As companies use more and more applications to manage business processes, provide new services, and gain an observation of business performance, the number of application servers and data storage servers required to support these applications is significantly increased. In many companies, the cost of hardware and the cost of deploying and maintaining multiple servers within the company are major financial and logistical budgets. At t