cascade dk

must state : This blog is reproduced in Oracle foreign KEY cascade DELETE and cascade update http://www.2cto.com/database/201507/417496.htmlIn view of the previous collection of wonderful blog has been deleted, it is very sad, so still want to copyFirst, cascade deleteOracle Delete on foreign keys has no action (similar to restrict),

In hibernate, the configuration file for persistent objects contains the cascade attribute, as the name implies, cascade, that is, when Operations on the current object will affect the associated entities configured accordingly. For example, when you save the current object The object associated with it. Of course, the generation of this additional operation depends on whether you have configured the elemen

Cascade:Cascading: An object's chain operationCascade Save:Cascade Save: When you save a party to a bidirectional relationship, the error is reported by default, and you should set the Cascade save in Customr, that is, when you manipulate an object by manipulating other associated objectsConfigure the cascading update at the customer end:cascade= "Save-update" classIn the test case, the value is manipulated for customer: Cust.getorders (). Add (O1)

Database transactionsStart transaction; #开始事务Insert into GZB (GZ) values (5000);Insert into GZB (GZ) VALUES (6000);Insert into GZB (GZ) values (7000);Insert into GZB (GZ) values (8000); /* Perform the transaction and see if success data is added */Commit # commit data to see if the data in the table is submittedRollback #数据库回滚Cascade UPDATE, Cascade DeleteThere are two main ways of1. When building the table

For more information about how to delete SQL cascading updates, see For more information about how to delete SQL cascading updates, see The Code is as follows:On delete cascade When you update or delete a primary key table, the foreign key table will be updated or deleted together. You need to set cascade attributes when creating the table. Create table Countries (CountryId int primary key)Insert into

Copy codeThe Code is as follows: on delete cascade When you update or delete a primary key table, the foreign key table will be updated or deleted together. You need to set cascade attributes when creating the table. Create table Countries (CountryId int primary key)Insert into Countries (CountryId) VALUES (1)Insert into Countries (CountryId) VALUES (2)Insert into Countries (CountryId) VALUES (3) Creat

Php + ajax cascade menu [no refreshing cascade menu]. The php + ajax cascade menu released by this netizen is often called refreshing. The php + ajax cascade menu released by this netizen is often called refreshing .? Phpheader (C, the php + ajax cascade menu released by a n

In the past, SQL Server only performed operations on the graphic interface. Now I find that my SQL language skills are getting worse and worse. For example, how to add associations for two tables, cascade update and delete. I checked it at night and found that two methods can be used. Trigger method:Create trigger trg_aOnFor update, deleteAsBeginIf exists (select 1 from inserted)Update B set name = (Select name from inserted) Where name = (Select nam

CSS: The weight and cascade rules determine its priority. css Cascade Source: http://www.ido321.com/1063.html First, let's look at an example of CSS priority: http://www.ido321.com/76.html I. basic priority rules Compare the number at the same level. If the number is the same, it has a higher priority. If the number is the same, compare the number at the lower level. The priority for each level is as follo

EasyUi + JS ---- ComboBox cascade and easyuicombobox Cascade Recently I am working on the effect of EasyUi ComboBox-Level Association. The related content is as follows: EasyUI is just getting started with JavaScript. I have learned it before. But I am still a newbie in how to use it. However, I am still learning it and practice it. This is the final principle. I will directly go to the Code: Front-end HTM

;importorg.junit.before;importorg.junit.test;import com.mycompany.demo.util.hbnutil;publicclasstestapp{privatesessionsession;@ Beforepublicvoidinit () {session=hbnutil.getsession ();} /** one-to-many bidirectional association-add * need to set the Set property in Forum.hbm.xml to Cascade= "All" */@Testpublic void testonetomanyadd () {try{session.begintransaction (); Forumpostforumpost1=newforumpost (); Forumpost1.setsubject ("A"); Forumpostforumpost2=

This is an optional database foreign key definition that sets the transformation rules for the response field in the Foreign key table when the data of the referenced column in the primary key table changes. Update is the value of the referenced field in the primary key table, and delete refers to the deletion of a record in the primary key table:On update and on Delete can be followed by four wordsNo action, set NULL, set default, CascadeNo action means no action,Set NULL indicates that the cor

The order of Flash and DIV cascade, flashdiv Cascade Many people encounter this problem when writing Page code, that is, when Flash overlaps with other HTML structures in the page, Flash is always displayed at the top by default, so as to block the HTML structure that overlaps with it, even if the z-index attribute is defined for the Flash or HTML structure tag, it is still invalid. By default, Flash files

Update: three-state cascade selection is supported.Download:/Files/boolean/checkbox3StatucCascadeSelectTree.zipOnline demonstration:/Files/boolean/cascadeTree.htm

About Inverse=true and Cascade in Hibernate Hibernate set mapping inverse and cascade detailed 1, in the end where to use Cascade= "...". Cascade attribute is not a many-to-many relationship must be used, with it just let us insert or delete to the image of more convenient, as long as the source of

1, exactly where to use cascade= "..."?Cascade property is not a many-to-many relationship must be used, with it just let us in the insertion or deletion of the image is more convenient, as long as the cascade at the source of the insertion or deletion, all cascade relationship will be inserted or deleted by themselves

1. Where can I use cascade = "..."? The cascade attribute is not required for many-to-many relationships. With this attribute, we only make it easier to insert or delete the object, as long as we insert or delete the object at the cascade source, all cascade relationships are automatically inserted or deleted. To ma

When there is a parent-child relationship between the two parties, you can set cascade to all-delete-orphan at set. The so-called parent-child relationship refers to the persistence cycle of the child controlled by the parent. The child object must be associated with a parent object. If a parent object is deleted, all associated child objects should be deleted cascade; if a child object is no longer associa

Parent-Child tables are often involved when adding, modifying, and deleting records in a database.For example, a province table and a city table have a foreign key province_id referenced to the primary key of the province table. In this way, we can regard the province table as a parent table and the city table as a sub table. The existence of city table records depends on the records of the province table. (In the example mentioned in this article, all the code is included in the attachment, so

Inverse and cascade in Hibernate, both of which are used in one-to-many (One-to-many) or many-to-many (many-to-many) relationships.As a general rule,inverse represents whether the relationship is maintained by itself, and cascade represents whether to perform cascading operations. Next, give a column to explain the relationship in more detail.Suppose there are t_department (departmental tables) and T_employ