java - Android - How to Create Sqlite database with Tables -

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• when sqliteopenhelper oncreate() / onupgrade() run? 10 answers

i need create database 3 tables , doing below:

public class databaseutils extends sqliteopenhelper {       private final context mycontext;         private sqlitedatabase database;         // database creation sql statement       private static final string create_table_cs = "create table "+ table_cs + "(" + column_cs + " text not null, " + column_ce_cid + " integer not null, "+ column_ce_pid +" integer not null);";       private static final string create_table_ss = "create table "+ table_ss + "(" + column_ss + " text not null, " + column_sub_cid + " integer not null, "+ column_sub_pid +" integer not null);";       private static final string create_table_as = "create table "+ table_as + "(" + column_as + " text not null, " + column_cid + " integer not null, "+ column_aid +" integer not null);";        public databaseutils(context context) {         super(context, database_name, null, database_version);         database_path =  environment.getdatadirectory().getabsolutepath() + "/" +"data/"+ context.getresources().getstring(r.string.app_package);         this.mycontext = context;       }        @override       public void oncreate(sqlitedatabase database) {         database.execsql(create_table_cs);         database.execsql(create_table_ss);         database.execsql(create_table_as);       }       @override       public void onupgrade(sqlitedatabase db, int oldversion, int newversion) {         log.w(databaseutils.class.getname(),"upgrading database version " + oldversion + " "+ newversion + ", destroy old data");         //db.execsql("drop table if exists " + table_comments);         oncreate(db);       } } 

and in activity calling databaseutils class in oncreate below:

databaseutils db = new databaseutils(this); 

but database not creating 3 tables. doing wrong? btw, have string values correctly. please me how create database.

i found solution. databaseutils' oncreate() never called if implement below:

 databaseutils db = new databaseutils(this); 

in myactivity's oncreate() method. need call getwritabledatabase() in myactivity below:

databaseutils db = new databaseutils(this); db.getwritabledatabase(); 

then databaseutils' oncreate() called , tables created.