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

1# #Example Example =New# #Example (); 2Example.setorderbyclause ("Field name ASC");//in ascending order, DESC is in descending order. 3Example.setdistinct (false)//Remove Duplicates, Boolean, True to select records that are not duplicates. 4Criteria =NewExample (). Createcriteria (); 5IsNULL; is notNULL; 6 equal to (value); n equal to (value); 7 GreaterThan (value);    Greaterthanorequalto (value); 8 LessThan (value);    Lessthanorequalto (value); 9 In (Item,item,item,...);    Not in (Item,item,item,...); TenLike ("%" +value+ "%") and not-like ("%" +value+ "%");  One between (value1,value2); not between (Value1,value2) A      -       -      the example functions for mapper in MyBatis: - intCountbyexample (userexample example) Thorws SQLException: Count by condition.  - intDeletebyprimarykey (Integer ID) thorws SQLException: Delete by primary key.  - intDeletebyexample (userexample example) Thorws SQLException: Delete by condition.  +string/Integer Insert (User record) Thorws SQLException: Insert (return value is ID value) - User Selectbyprimarykey (Integer ID) thorws SQLException: Queries by primary key.  +List<?>Selectbyexample (userexample example) THORWS SQLException: query by Condition AList<?>Selectbyexamplewithblogs (userexample example) Thorws SQLException: Press at      - conditional queries (including BLOB fields).    Only if the field type in the data table is binary is it generated.  - intUpdatebyprimarykey (User record) Thorws SQLException: Update by primary key - intupdatebyprimarykeyselective (User record) Thorws SQLException: Update by primary key -      - a field with a value other than null in intupdatebyexample (User record, userexample example) Thorws SQLException: -      to Update by Condition + intupdatebyexampleselective (User record, userexample example) Thorws -      the SQLException: Updating a field with a value that is not NULL by condition *      $ The example functions of Mapper in MyBatis are detailed:Panax Notoginseng ①selectbyprimarykey () -      theUser user = # #Mapper. Selectbyprimarykey (100); Equivalent to select *From user where +      AID = 100 the      + ②selectbyexample () and Selectbyexamplewithblogs () -      $userexample example =Newuserexample ();  $Criteria =Example.createcriteria ();  -Criteria.andusernameequalto ("Joe");  - Criteria.andusernameisnull ();  theExample.setorderbyclause ("Username asc,email desc");  -List<?>list =# #Mapper. Selectbyexample (example); WuyiEquivalent to: SELECT * from user where username = ' Joe ' and username areNULLOrder the      - by username Asc,email desc Wu      - Note: The ibator generated file Userexample.java contains a static internal class Criteria, About      $ There are a number of methods in the criteria, primarily defining the query criteria after the SQL statement where.  -      - ③insert () -      AUser User =NewUser ();  +User.setid (101);  theUser.setusername ("Test");  -User.setpassword ("123")     $User.setemail ("[Email protected]");  the # #Mapper. Insert (user);  the equivalent to: INSERT INTO user (Id,username,password,email) values the      the(101, ' Test ', ' 123 ', ' [email protected] ');  -      in ④updatebyprimarykey () and updatebyprimarykeyselective () the      theUser User =NewUser ();  AboutUser.setid (101);  theUser.setusername ("Joe");  theUser.setpassword ("Joe");  theUser.setemail ("[Email protected]");  + # #Mapper. Updatebyprimarykey (user);  -Equivalent: Update user set username= ' Joe ', password= ' Joe ', email= ' [email protected] ' the     Bayiwhere id=101 the      theUser User =NewUser ();  -User.setid (101);  -User.setpassword ("Joe");  the # #Mapper. updatebyprimarykeyselective (user);  theEquivalent: Update user set password= ' Joe ' where id=101 the      the ⑤updatebyexample () and updatebyexampleselective () -      theuserexample example =Newuserexample ();  theCriteria =Example.createcriteria ();  theCriteria.andusernameequalto ("Joe"); 94User User =NewUser ();  theUser.setpassword ("123");  the # #Mapper. updatebyprimarykeyselective (User,example);  theEquivalent: Update user set password= ' 123 ' where username= ' Joe '98      About ⑥deletebyprimarykey () -     101# #Mapper. Deletebyprimarykey (101); Equivalent to: Delete from user where id=101102     103 ⑦deletebyexample ()104      theuserexample example =Newuserexample (); 106Criteria =Example.createcriteria (); 107Criteria.andusernameequalto ("Joe"); 108 # #Mapper. Deletebyexample (example); 109Equivalent to: Delete from user where username= ' Joe ' the     111 ⑧countbyexample () the     113userexample example =Newuserexample ();  theCriteria =Example.createcriteria ();  theCriteria.andusernameequalto ("Joe");  the intCount =# #Mapper. Countbyexample (example); 117Equivalent to: SELECT COUNT (*) from user where username= ' Joe '

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