Ten SQL Server DBA errors

SQLSERVERDBA can easily make ten mistakes. tvtop-10-administrative-mistakes-on-sql-server in addition to the top ten errors, other top errors aside from SQL Server errors, these errors are mainly reflected in the development or design: 1, unreasonable specifications and

SQL Server DBA easy to make ten mistakes in addition to the top ten errors in http://sqlsentry. TV /top-10-administrative-mistakes-on-sql-server/, other top errors aside from SQL Server errors, these errors are mainly reflected in the development or design process: 1. unreasonable specifications and

SQLSERVER DBA EasyTen criminals Error

From: http://sqlsentry. TV /top-10-administrative-mistakes-on-sql-server/

Except for the top 10ErrorOther top rankingError

Aside from SQL ServerError, TheseErrorIt is mainly reflected in development or design:

1. unreasonable specifications and unreasonable Database Design

2. There is no need to design good scalability.

3. No database performance baseline or benchmark

4. index problems

5. Insufficient emphasis on statement Optimization

ErrorLast 10 bits (Disk-I/O is ignored if the disk space is sufficient)

Only disk space of the disk subsystem is often considered, and I/O load is ignored.

If you do not have sufficient professional knowledge, the following problems may occur:

Improper fault tolerance mechanism selected

Insufficient IO performance:

OLTP systems require high TPS

OLAP requires high transmission speed

Select poor RAID type, Controller, and channel

Insufficient disk Spindle

Ssd ssds can change the rules of this IO game

ErrorNinth to last (Not Understanding Business Rules)

As an it pro, you should know how SQL Server works internally.

What is checkpoint? What is Lazy writer?

How does TempDB work? What is in plan cache?

You need to know that DBA is the protector of enterprise asset data

The connection between business and IT, you should know how and how to use your server

When the program goes down, who cares about the cost of downtime per minute?

What is the business cycle?

When is the best downtime?

What kind of baselines and baselines are normal?

ErrorThe last eight digits (There is no troubleshooting method of its own.)

In critical situations, DBAs need a powerful, step-by-step approach for root cause analysis.

If not, you will:

1. Missed the databaseErrorAnd problems

2. BecauseErrorData loss or catastrophic problems

3. Poor response time or violation of SLA

4. loss of credibility

If you do not have a methodology, you can refer

End-to-End Troubleshooting on http://SQLSentry. TV

SQL Server Troubleshooting Guide by J. Kehayias on http://www.simple-talk.com

ErrorThe last 7 digits (basically the default value is used))

The purpose of installing SQL Server by default is to enable the Server to start and run as soon as possible.

However, this will result in a lack of optimal runtime, such as the following settings:

Automatic database growth and contraction

Automatically increasing database size

Default file group

Some minor problems will also become major problems

1. Degree of Parallelism

2. Fill Factor

Other settings for servers and databases

ErrorThe last six digits (remember the security of the database after the event))

The SQL injection vulnerability on the Internet is now the first

It is worth noting that many anti-SQL injection methods have been in use for the past 10 years.

We plan to minimize the problem in advance:

Make sure that the application running on your server has only the minimum permissions, and this permission can ensure that your program runs normally.

How many exposed servers are there? More exposed and more attacked

Who has the right to access your server?

When something goes wrong, how do you find out who has opened some inappropriate permissions?

ErrorFifth to last (not fully automated)

Automation can reduce DBA's work. The irony is that at the beginning, DBA needs to automate a lot of work.

Without automation, DBAs must face the following problems:

It is possible to perform operations by people.EasyErrors and omissions

When the number of servers increases, your work will be doubled.

Example of automation:

Automatic Error Notification

Maintain scheduled jobs

Basically, scripts are used instead of the GUI.

ErrorLast-to-last position (using inappropriate functions or technologies at work)

DBA is the "performance engineer" of the company's IT program"

His job is to use the most appropriate features for each business needs

Otherwise:

Complex applications

Excessive Resource Consumption

There is a theorem: There is no IT project, and only IT is used to solve commercial projects.

ErrorLast three places (indifferent to management changes)

Change management is very important! If no change is managed, the dba will face:

If they do not change, what they do will be worse.

Change control manages changes

Reasonable management changes mean:

Pre-plan the time in the specified time limit

In the production environment, management changes are verified and tested.

Changes are isolated, atomic, and reversible.

ErrorSecond to last (inappropriate maintenance plan)

Appropriate preventive maintenance (PM) can help you:

Catch the problem before it occurs

Determine the Optimization Direction

Resource-intensive operations on the system will be reduced.

Preventive Maintenance should include

Database consistency check and DBCC CHECKIDENT

Use the verification option to back up and restore the database

Index fill factor and fragmentation

Index statistics

Do not rely on the database maintenance plan wizard !!

There is no need to repeat the wheel. There are a lot of maintenance plans that have been written by XianRen for us.

Www.sqlfool.com

Www.olahallengren.com

ErrorLast (backup and restoration))

DBA does not often verify the backup availability

This will cause some problems:

Your SLA to the customer is not guaranteed, and RTO and RPO are not guaranteed.

No one can ensure the backup is available

If anything is wrong, you are welcome to make a brick o