bulk update

XML file configuration under normal spring:XML version= "1.0" encoding= "UTF-8"?> DOCTYPE Configuration Public "-//mybatis.org//dtd Config 3.0//en" "Http://mybatis.org/dtd/mybatis-3-config.dtd" > Configuration> Set Run Parameters -

Lock mode Lock mode Description Share (S) Used for read operations that do not change or do not update data, such as a SELECT statement. Update (U) Used in resources that can be updated.

1 PrefaceThe database large concurrency operation takes into account the deadlock and lock performance issues. See online most vague (especially update lock), so here is a concise explanation, for the following description of the convenient, here

1. Bulk Update InsertsJdbctemplate.batchupdate (String sql, list Batchargs)Object[] The length of the array is the number of arguments per record (i.e. "?" in the SQL statement). Number of)List: How many records are inserted in total./** * BULK

When users modify the layout, they need to update the MySQL xxxx_layout_xxxx table in bulk. The volume of data for a bulk operation is 2-30/times. Batch operation is a key point in the technology of the project, before the batch operation has done

Although there are SQL standards, each relational database will eventually be unique, so you need to tune the data access layer to take advantage of the relational database in use.In this article, we'll show you what we can do to improve performance

One: The concept of the lockAccording to the Writing technology blog, should be the concept of the lock to do an introduction, I think, can click into this blog students, presumably have heard of the lock. So I try to express it in concise

1 PrefaceThe database large concurrency operation takes into account the deadlock and lock performance issues. See online most vague (especially update lock), so here is a concise explanation, for the following description of the convenient, here

Today encountered a problem is to bulk update the value of a field in the database, you need to find out which table contains this field, organized the following statement to facilitate querySELECT

When working with database transactions, some operations can produce errors, and errors can result in unpredictable operations, especially in bulk transactions. In order to avoid this situation, it is necessary to control the data connection and

In the actual project development, sometimes need to send a batch of SQL statement execution to the database, should avoid to send execution to the database, and should adopt the batch processing mechanism of JDBC, in order to improve the execution

Database bulk Update.Business requirements:You need to update the source_id of the Type 1 data in table A to the new ID.Because the previous ID was stored in p_server, it is now updated to the Server_info tableUpdate a set source_id = s.server_id

Overview of LocksI. Why to introduce a lockConcurrent operations on a database by multiple users can lead to inconsistencies in the following data:Missing updatesA, a, two users read the same data and modify it, and one of the user's modifications

Recently, the development system used SqlServer2008 R2, but due to the increase of the system data pressure, ready to add a database synchronized with the official databases, used for the interface and reports to use, so began to the SQL Server in

1 PrefaceThe database large concurrency operation takes into account the deadlock and lock performance issues. See online most vague (especially update lock), so here is a concise explanation, for the following description of the convenient, here

Background Recently to XX to do the project, the most headache here is the database storage bottleneck problem. Environment Server environment: Virtual machine, allocate 32CPU, disk 1.4t,4t,5t,6t several servers are not equivalent

Overview of LocksI. Why to introduce a lockConcurrent operations on a database by multiple users can lead to inconsistencies in the following data:Missing updatesA, a, two users read the same data and modify it, and one of the user's modifications

SQL starts to execute slowly, because long SQL executions block many other sqls.Check approach:There is reports that can is generated from within Management Studio for blocking transactions and long running SQL.Solutions:Find the blocker SQL with

Student class Package Com.test.hou.po;public class Student {private int sid;private String sname;private int sage;public int GetSID () {R Eturn SID;} public void Setsid (int sid) {this.sid = SID;} Public String Getsname () {return sname;}

When we save the data into the database will probably use a script such as PHP to get a time to save to MySQL, in fact, MySQL can directly use the timestamp data type to implement the default type, the next look.Many times, in order to be simple, we