sorts

Data | database | performance Database Performance Check Guidance program Author:kamus Date:2004-9 After the system is stabilized, the product database should be inspected once a month in accordance with this guidance plan. This guidance

Today, I was discussing with my friends the following topics: "There is a table on the index, drop the table, and flash back to delete back, excuse me, the index on this table can still use?" If there's a change, what is it? 》 I conducted the

Excel is sorted by date of birth as follows: Method One: Auxiliary column + formula For example, the following table is a list of employee birth dates for a company, the name is in the A2:a18 area, and the date of birth is in the B2:b18 area.

web| Page | Optimization example of Web page-turning optimization Author: Wanghai Environment: Linux version 2.4.20-8custom (ROOT@WEB2) (gcc version 3.2.2 20030222 (Red Hat Linux 3.2.2-5)) #3 SMP Thu June 5 22:03:36 CS T 2003 mem:2113466368

Look at a simple example: Sql> CREATE TABLE T as 2 SELECT * from Dba_objects; Table has been created. Sql> SET Autot on Sql> SELECT COUNT (*) from T; COUNT (*) ---------- 49611 Execution plan ------------------------------------------------

oracle| Performance | optimization 36. Replace or with union (applicable to indexed columns) In general, replacing or in a WHERE clause with union would have a better effect. Using or for an indexed column causes a full table scan. Note that the

Do stationmaster each is very not easy, because the website needs to optimize, the promotion, the maintenance, the renewal, the analysis and so on forest all sorts of problems need to solve, moreover for the personal stationmaster, is every day has

PHP multidimensional array sorting can be handled using the Array_multisort () function, which can be used to sort multiple arrays at once, or to sort multidimensional arrays based on one dimension or multidimensional, and the associated (string)

Data | database | performance Storage performance Assessment When storing performance evaluations, we use the Disk Performance index (DPI, disk Performance Index), and the following table lists the indices in the DPI, which do not imply a full

Index is a common database object, it is set up and used properly, which greatly affects the performance of database applications and databases. Although there is a lot of data on the use of indexing, DBAs and developer often deal with it, but the

mysql| Security | Security as a MySQL system administrator, you are responsible for maintaining the data security and integrity of your MySQL database system. This article mainly describes how to build a secure MySQL system, from the system internal

When you are learning Oracle, you may experience an Oracle index scan problem, and here's how to solve the Oracle index scan problem, and share it here. There are 4 types of Oracle index scans, depending on the type of index and the WHERE constraint:

2. Cross-partitioned access is still a good performance for partitioned tables, because the data is concentrated in 2 partitions or more than the access T1 to access data less ... Sql> SELECT * from t1 where object_id 504448 rows have been

mysql| Security | access | server | data | database | Network MySQL security system is flexible. It allows you to set user access rights in many different ways. Typically, the grant and REVOKE statements are used to modify the authorization table

  This article mainly introduces the asp.net + ajax + SQL Server automatic complement function, the need for friends can refer to the following Code download Description: Database connection string in Web.config file, the official Northwind

Oracle Indexes (index) is a common database object that is set up and used properly, which greatly affects the performance of database applications and databases. Although there is a lot of data on the use of indexing, DBAs and Developer often deal

Function Description: Sort the contents of the text file. Syntax: Sort [-bcdfimmnr][-o][-t][+-][--help][--verison][file] Supplemental Note: Sort can be sorted against the contents of a text file in units of behavior. Parameters -B ignores the

Random Oracle provides sample table scanning features starting from oracle8i. Oracle's basic methods of accessing data are: 1. Full table Scan 2. Sampling table Scanning Full table scan (Scan) The full table scan returns all the records in the

A brief introduction to the characteristics of OLTP and OLAP systems A: OLTP and OLAP are the 2 most commonly used systems in our daily production libraries, and simply say that OLTP is a system based on a multiple transaction short time slice, and

When you write an MFC program some time ago, you need to sort a string collection CStringArray. The Standard Template Library STL provides a function template sort that is powerful but has two inconveniences: 1. Sort uses the enumerator (iterator)