Database Cursor Example

A good database product is not equal to have a good application system, if can not design a reasonable database model, not only will increase the client and Server section program programming and maintenance of the difficulty, and will affect the actual performance of the system. Generally speaking, in an MIS system analysis, design, test and trial run stage, because the data quantity is small, designers and testers often only notice the realization of the function, but it is difficult to notice the weak performance, until the system put into actual operation for some time, only to find that the performance of the system is decreasing, At this point to consider improving the performance of the system will cost more ...

As long as you master the following method, you can basically get the mysql database. First, the connection MYSQL format: mysql-h host address-u username-p user password 1, Example 1: Connect to the local MySQL: First open the DOS window and then enter the directory mysqlbin, then type the command mysql -uroot - p, after the carriage return prompts you to lose the password, if you just installed MYSQL, super user root is no password, so enter directly into MYSQL, MYS ...

Logminer is an actual, useful analysis tool that Oracle has provided since 8i, which makes it easy to obtain specific content in Oracle Redo log files (archived log files), Logminer analysis tools are actually made up of a set of PL 　　SQL package and a number of dynamic views that can be used to analyze online logs and archive logs to obtain a database of past detailed, specific operations, very useful. 　　Why do you use Logminer? Mainly for the following reasons: When the database occurs ...

Logminer is an actual, useful analysis tool that Oracle has provided since 8i, which makes it easy to obtain specific content in Oracle Redo log files (archived log files), Logminer analysis tools are actually made up of a set of PL SQL package and a number of dynamic views that can be used to analyze online logs and archive logs to obtain a database of past detailed, specific operations, very useful. Why do you use Logminer? Mainly for the following reasons: When the database has been mistakenly operated, need not be completed ...

Intermediary transaction http://www.aliyun.com/zixun/aggregation/6858.html ">seo diagnose Taobao guest cloud host technology Hall some time ago, the company a main web site database of individual table data is often modified and hanging horse, Since the site was previously done by someone else, the code was a bit messy, so I only looked at the file code associated with these tables. The reason for this may be that when the parameters are received, no dangerous characters are filtered, and the format function is added to accept the parameters ...

MySQL database sql statement commonly used optimization methods 1. Query optimization, should try to avoid full table scan, should first consider where and order by the columns involved in the establishment of the index. 2. Should be avoided in the where clause on the field null value judgment, otherwise it will cause the engine to abandon the use of indexes and full table scan, such as: select id from t where num is null You can set the default value of num 0, to ensure that Num column table does not null value ...

Intermediary trading http://www.aliyun.com/zixun/aggregation/6858.html ">seo diagnose Taobao guest Cloud host Technology Hall I recently in the operation of a Non-mainstream station, the content is collected, began to collect fortunately, later was K, Tens of thousands of data station Baidu included only dozens of. Of course, I also know that the collection is not the way, but the manpower is limited, it is impossible to add, nor realistic. So want to search the search engine is how to determine the original ...

Intermediary trading http://www.aliyun.com/zixun/aggregation/6858.html ">seo diagnose Taobao guest Cloud host Technology Hall I recently in the operation of a Non-mainstream station, the content is collected, began to collect fortunately, later was K, Tens of thousands of data station Baidu included only dozens of. Of course, I also know that the collection is not the way, but the manpower is limited, it is impossible to add, nor realistic. So want to search the search engine is how to judge the original ...

NoSQL Recent momentum is good, http://www.aliyun.com/zixun/aggregation/13461.html ">mongodb is one of the Jiao jiao, oneself learn nosql when also reference a lot of information, The final decision to start from the MongoDB, the most important reason has two: 1 oneself is a simple amateur, all problems I think whether there is a simple way to solve, rather stop to think a lot of time, also do not want to use stupid method to do immediately, and Mong ...

Using Redis to develop applications is a pleasant process, but as with other technologies, you need to remember a few things as well, based on Redis application design. Before, you might have a chest of the whole pattern of relational database development, and REDIS application development has many similarities, but you have to keep in mind that the following two points--redis is a memory database, and it is single-threaded. Therefore, when using Redis, you need to pay attention to the following points: 1. Master all key databases stored in Redis ...