Android Code Implementation View tables in the SQLite database

Objective

Before writing PHP, built-in print_r() and var_dump() two functions for the printout of any type of data internal structure, now do the development of Android, found that there is no such a function, for the database view is not convenient, so wrote a look at the database table method code.

Code implementation

ImportJava.util.Arrays;Importandroid.app.Activity;ImportAndroid.database.Cursor;ImportAndroid.database.sqlite.SQLiteDatabase;ImportAndroid.os.Bundle;ImportAndroid.util.Log;ImportAndroid.view.View;ImportAndroid.view.View.OnClickListener;ImportAndroid.widget.Button; Public  class secondactivity extends Activity {     Public Static FinalString TAG ="Debug Info";@Override    protected void onCreate(Bundle savedinstancestate) {Super. OnCreate (Savedinstancestate); (Button) Findviewbyid (R.id.btnque)). Setonclicklistener (NewOnclicklistener () {@Override             Public void OnClick(View v) {Mydatabasehelper DBHelper =NewMydatabasehelper (secondactivity. This,"Bookstore.db",NULL,1); Sqlitedatabase db = Dbhelper.getwritabledatabase ();//Core area                //Read system table Sqlite_masterString sql ="SELECT * from Sqlite_master"; cursor cursor = db.rawquery (SQL,NULL);//Print all column names of the tableLOG.I (TAG, Arrays.tostring (Cursor.getcolumnnames ()));//Print all tables in the current database                if(Cursor.movetofirst ()) {do {String str =""; for(String item:cursor.getColumnNames ()) {str + + item +": "+ cursor.getstring (Cursor.getcolumnindex (item)) +"\ n";                    } log.i (TAG, str); } while(Cursor.movetonext ());    }            }        }); }}

Feature Extensions

To see if a table exists

 PublicBooleantableisexist(Sqlitedatabase db, String tableName) {Booleanresult =false; cursor cursor =NULL;if(TableName = =NULL){returnResult } String sql ="SELECT COUNT (*) from sqlite_master where type = ' table ' and name = '"+tablename.trim () +"'"; cursor = db.rawquery (SQL,NULL);if(Cursor.movetonext ()) {if(Cursor.getint (0) >0) {result =true; }    }returnResult;}

See which tables are in the database

publictablesInDB(SQLiteDatabase db){    new ArrayList<String>();    "select name from sqlite_master where type=‘table‘";    null);    if (cursor.moveToFirst()) {            do {                list.add(cursor.getString(0));            while (cursor.moveToNext());        }    return list;}

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Android Code Implementation View tables in the SQLite database