Mapper interface files in MyBatis and instance functions of the example class and detailed

2. # #Example Example = new # #Example ();
4. Example.setorderbyclause ("field name ASC");    //in ascending order, desc in descending order.
6. Example.setdistinct (false)//Remove Duplicates, Boolean, True to select records that are not duplicates.
8. Criteria = new Example (). Createcriteria ();
10. is null;is not null;
12. Equal to (value); n equal to (value);
14. GreaterThan (value); Greaterthanorequalto (value);
16. LessThan (value); Lessthanorequalto (value);
18. In (Item,item,item,...); Not in (Item,item,item,...);
20. Like ("%" +value+"%") and not-like ("%" +value+"%");
22. Between (value1,value2); not between (Value1,value2)
30. Example functions for mapper in MyBatis:
32. int Countbyexample (userexample example) Thorws SQLException: counts by condition.
34. int Deletebyprimarykey (Integer id) thorws SQLException: Delete by primary key.
36. int Deletebyexample (userexample example) Thorws SQLException: Delete by condition.
38. String/integer Insert (User record) Thorws SQLException: Insert (return value is ID value)
40. User Selectbyprimarykey (Integer ID) thorws SQLException: Queries by primary key.
42. List<?>selectbyexample (userexample example) THORWS SQLException: Query by condition
44. List<?>selectbyexamplewithblogs (userexample example) Thorws SQLException: Press
48. Conditional queries (including BLOB fields). Only if the field type in the data table is binary is it generated.
50. int Updatebyprimarykey (User record) Thorws SQLException: Update by primary key
52. int updatebyprimarykeyselective (User record) Thorws SQLException: Update by primary key
56. a field with a value other than null
58. int Updatebyexample (User record, userexample example) Thorws SQLException:
62. Update by condition
64. int updatebyexampleselective (User record, userexample example) THORWS
68. SQLException: Updating a field with a value that is not NULL by condition
72. The example functions of Mapper in MyBatis are detailed:
74. ①selectbyprimarykey ()
78. User user = # #Mapper. Selectbyprimarykey (100); equivalent to select * from user where
82. id =
86. ②selectbyexample () and Selectbyexamplewithblogs ()
90. userexample example = new Userexample ();
92. Criteria = Example.createcriteria ();
94. Criteria.andusernameequalto ("Joe");
96. Criteria.andusernameisnull ();
98. Example.setorderbyclause ("username asc,email desc");
100. list<?>list = # #Mapper. Selectbyexample (example);
102. Equivalent to: SELECT * from user where username = ' Joe ' and username are null order
106. by username Asc,email desc
110. Note: The ibator generated file Userexample.java contains a static internal class Criteria,
114. There are a number of methods in the criteria, primarily defining the query criteria after the SQL statement where.
118. ③insert ()
122. User user = new user ();
124. User.setid (101);
126. User.setusername ("test");
128. User.setpassword ("123")
130. User.setemail ("[email protected]");
132. # #Mapper. Insert (user);
134. Equivalent to: INSERT INTO user (Id,username,password,email) values
138. (101,' test ',' 123 ',' [email protected] ');
142. ④updatebyprimarykey () and updatebyprimarykeyselective ()
146. User user =new user ();
148. User.setid (101);
150. User.setusername ("Joe");
152. User.setpassword ("Joe");
154. User.setemail ("[email protected]");
156. # #Mapper. Updatebyprimarykey (user);
158. Equivalent: Update user set username=' Joe ', password=' Joe ', email=' [email protected] '
162. where id=101
166. User user = new user ();
168. User.setid (101);
170. User.setpassword ("Joe");
172. # #Mapper. updatebyprimarykeyselective (user);
174. Equivalent: Update user set password=' Joe ' where id=101
178. ⑤updatebyexample () and updatebyexampleselective ()
182. userexample example = new Userexample ();
184. Criteria = Example.createcriteria ();
186. Criteria.andusernameequalto ("Joe");
188. User user = new user ();
190. User.setpassword ("123");
192. # #Mapper. updatebyprimarykeyselective (User,example);
194. Equivalent: Update user set password=' 123 ' where username=' Joe '
198. ⑥deletebyprimarykey ()
202. # #Mapper. Deletebyprimarykey (101); Equivalent to: Delete from user where id=101
206. ⑦deletebyexample ()
210. userexample example = new Userexample ();
212. Criteria = Example.createcriteria ();
214. Criteria.andusernameequalto ("Joe");
216. # #Mapper. Deletebyexample (example);
218. Equivalent to: Delete from user where username=' Joe '
222. ⑧countbyexample ()
226. userexample example = new Userexample ();
228. Criteria = Example.createcriteria ();
230. Criteria.andusernameequalto ("Joe");
232. int count = # #Mapper. Countbyexample (example);
234. Equivalent to: SELECT COUNT (*) from user where username=' Joe '
     

Mapper interface files in MyBatis and instance functions of the example class and detailed