Android in-depth study of SQLite instances (IV)

Written in front of, this article Reprinted from http://www.eoeandroid.com/thread-81914-1-1.html

// Delete the last character sb. deletecharat (sb. length ()-1); sqlitedatabase database = dbmanger. getwritabledatabase (); // execsqlis the execution of SQL statement database.exe csql ("delete from person where personid in (" + Sb + ")", (object []) IDs );}} // query by page a public list getdateperson (INT startresult, int maxresult) {list persons = new arraylist (); sqlitedatabase database = dbmanger. getwritabledatabase (); // cursor is a cursor type. A cursor is actually a dataset in the database. // rawquery (string SQL, strin G [] S) parameter 1 is an SQL statement parameter 2 is a specific value stored in the condition placeholder in parameter 1 SQL statement. These values are a string array cursor = database. rawquery ("select * From person limit ?,? ", New string [] {string. valueof (startresult), String. valueof (maxresult)}); While (cursor. movetonext () {persons. add (new person (cursor. getint (0), cursor. getstring (1), cursor. getshort (2);} return persons;} // two public cursor getdaterawperson (INT startresult, int maxresult) {// list persons = new arraylist (); sqlitedatabase database = dbmanger. getwritabledatabase (); // cursor is a cursor type. A cursor is actually a dataset in the database. // rawquery (stri Ng SQL, string [] S) parameter 1 is an SQL statement parameter 2 is a specific value stored in the condition placeholder in parameter 1 SQL statement. These values are a string array return database. rawquery ("select personid AS _ id, name, age from person limit ?,? ", New string [] {string. valueof (startresult), String. valueof (maxresult)});} // obtain the total number of records public long getcount () {sqlitedatabase database = dbmanger. getwritabledatabase (); // cursor is a cursor type. cursor is actually a data set in the database. cursor = database. rawquery ("select count (*) from person", null); If (cursor. movetolast () {return cursor. getlong (0) ;}return 0 ;}}

Business type 2

Package EOE. demo; import Java. util. arraylist; import Java. util. list; import it. bean. person; import android. content. contentvalues; import android. content. context; import android. database. cursor; import android. database. SQLite. sqlitedatabase; /*** this class does not require addition, deletion, query, modification, and modification operations based on SQL statements * But the sqlitedatabase object is operated by constructing an SQL statement internally **/public class personsqlservice {private mangerdatabase dbmanger; public personsqlservice (context contex T) {dbmanger = new mangerdatabase (context);} public void save (person) {sqlitedatabase database = dbmanger. getwritabledatabase (); contentvalues values = new contentvalues (); values. put ("name", person. getname (); values. put ("Age", person. getage (); // name of the parameter table to construct the correct field ing database for the insert statement. insert ("person", "name", values);} public void Update (person) {sqlitedatabase database = dbmanger. getwritabledat Abase (); contentvalues values = new contentvalues (); values. put ("name", person. getname (); values. put ("Age", person. getage (); // parameter table name update ing relationship condition placeholder value database. update ("person", values, "personid =? ", New string [] {string. valueof (person. getpersonid ()});} public person find (integer ID) {sqlitedatabase database = dbmanger. getwritabledatabase (); // execute the query parameter. The fields returned by the table name specify the condition and specify whether the condition values are grouped or not. query ("person", new string [] {"personid", "name", "Age"}, "personid =? ", New string [] {string. valueof (ID)}, null); If (cursor. movetonext () {return new person (cursor. getint (0), cursor. getstring (1), cursor. getshort (2);} return NULL ;}