Android SQLite basic operations, androidsqlite

Android SQLite basic operations, androidsqlite

Add, delete, modify, and query related to SQLite are displayed in log.

Package com. example. sqlconnecttest; import android. content. context; import android. database. sqlite. SQLiteDatabase; import android. database. sqlite. SQLiteDatabase. cursorFactory; import android. database. sqlite. SQLiteOpenHelper; import android. util. log; public class DBHelper extends SQLiteOpenHelper {/** required constructors */public DBHelper (Context context, String name, CursorFactory factory, int version) {super (context, name, factory, version);}/** this method is called when a database is created for the first time */@ Overridepublic void onCreate (SQLiteDatabase db) {Log. I ("createDatabases", "CREATE DATABASE --->") ;}/ ** call this method when updating the database */@ Overridepublic void onUpgrade (SQLiteDatabase db, int oldVersion, int newVersion) {Log. I ("updateDatabase", "update database ---> ");}}

 

Package com. example. sqlconnecttest; import android. app. activity; import android. content. contentValues; import android. database. cursor; import android. database. SQLException; import android. database. sqlite. SQLiteDatabase; import android. OS. bundle; import android. util. log; import android. view. view; import android. view. view. onClickListener; import android. widget. button; public class MainActivity extends Activity Implements OnClickListener {private Button createDatabase; private Button createTable; private Button insert; private Button select; private Button update; private Button delete; private final String DATABASE_NAME = "myDatabase "; private SQLiteDatabase mySQLiteDatabase = null; private final String TABLE_NAME = "user"; private String SQL = "CREATE TABLE [user] (" + "[id] INTEGER NOT NULL PRIMARY KEY autoinre MENT, "+" [username] varchar not null, "+" [password] varchar not null, "+" [phoneNumber] varchar not null) "; private DBHelper db; @ Overrideprotected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. main); createView (); setListener ();} private void createView () {createDatabase = (Button) findViewById (R. id. createDatabase); createTable = (Button) findView ById (R. id. createTable); insert = (Button) findViewById (R. id. insert); select = (Button) findViewById (R. id. select); update = (Button) findViewById (R. id. update); delete = (Button) findViewById (R. id. delete);} // Add the listener private void setListener () {createDatabase. setOnClickListener (this); createTable. setOnClickListener (this); insert. setOnClickListener (this); select. setOnClickListener (this); update. setOnClickListener (This); delete. setOnClickListener (this);} // various listening Methods @ Overridepublic void onClick (View view) {switch (view. getId () {case R. id. createDatabase: {db = new DBHelper (MainActivity. this, DATABASE_NAME, null, 1); mySQLiteDatabase = db. getWritableDatabase (); Log. I ("database object", mySQLiteDatabase. toString (); // System. out. print ("database object" + mySQLiteDatabase); break;} case R. id. createTable: {db = new DBHelper (MainActivity. this, DATABA SE_NAME, null, 1); mySQLiteDatabase = db. getWritableDatabase (); try using mysqlitedatabase.exe cSQL (SQL); Log. I ("create table", SQL);} catch (SQLException e) {e. printStackTrace (); Log. I ("Create a table --", "failed to create a table --------------" ");} break;} case R. id. insert: {db = new DBHelper (MainActivity. this, DATABASE_NAME, null, 1); mySQLiteDatabase = db. getWritableDatabase (); ContentValues cv = new ContentValues (); cv. put ("username", "Dad"); cv. Put ("password", 123456); cv. put ("phoneNumber", "134756658888"); long n = mySQLiteDatabase. insert (TABLE_NAME, null, cv); Log. I ("insert data", n + ""); mySQLiteDatabase. close (); break;} case R. id. select: {db = new DBHelper (MainActivity. this, DATABASE_NAME, null, 1); mySQLiteDatabase = db. getReadableDatabase ();/*** parameter 1: Table name * parameter 2: column to be displayed * parameter 3: where statement * parameter 4: where statement condition value * parameter 5: grouping Mode * parameter 6: having condition * parameter 7: Sorting mode */Cursor cu Rsor = mySQLiteDatabase. query (TABLE_NAME, new String [] {"id", "username", "password", "phoneNumber"}, null, null ); while (cursor. moveToNext () {int id = cursor. getInt (cursor. getColumnIndex ("id"); String username = cursor. getString (cursor. getColumnIndex ("username"); String password = cursor. getString (cursor. getColumnIndex ("password"); String phoneNumber = cursor. getString (cursor. getColum NIndex ("phoneNumber"); Log. I ("query -->", "id:" + id + "userName:" + username + "password" + password + "phoneNumber" + phoneNumber);} mySQLiteDatabase. close (); break;} case R. id. update: {db = new DBHelper (MainActivity. this, DATABASE_NAME, null, 1); mySQLiteDatabase = db. getWritableDatabase (); ContentValues cv1 = new ContentValues (); cv1.put ("username", "admin"); cv1.put ("password", "admin"); cv1.put ("phone Number "," 1388888 "); String whereClause =" id "+" =? "; String [] whereArgs = {" 8 "};/** parameter 1: Table name * parameter 2: A ContextValue object, which is the updated value * parameter 3: where statement condition * parameter 4: where condition value */int index = mySQLiteDatabase. update (TABLE_NAME, cv1, whereClause, whereArgs); Log. I ("update -->", index + ""); break;} case R. id. delete: {db = new DBHelper (MainActivity. this, DATABASE_NAME, null, 1); mySQLiteDatabase = db. getWritableDatabase ();/***** parameter 1: Table name * parameter 2: where statement field * parameter 3: where statement field value */String WhereClause1 = "id" + "=? "; String [] whereArgs1 = {" 1 "}; int num = mySQLiteDatabase. delete (TABLE_NAME, whereClause1, whereArgs1); Log. I ("delete record -->", num + ""); mySQLiteDatabase. close (); break;} default: break ;}}}

<RelativeLayout xmlns: android = "http://schemas.android.com/apk/res/android" xmlns: tools = "http://schemas.android.com/tools" android: layout_width = "match_parent" android: layout_height = "match_parent" android: paddingBottom = "@ dimen/activity_vertical_margin" android: paddingLeft = "@ dimen/plugin" android: paddingRight = "@ dimen/plugin" android: paddingTop = "@ dimen/plugin" tools: context = "com. example. sqlconnecttest. mainActivity "> <TextView android: id =" @ + id/textView "android: layout_width =" wrap_content "android: layout_height =" wrap_content "android: text = "SQLite Database"/> <Button android: id = "@ + id/createDatabase" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_below = "@ id/textView" android: text = "Create a database"/> <Button android: id = "@ + id/createTable" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_below = "@ id/createDatabase" android: text = "Create a table"/> <Button android: id = "@ + id/insert" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_below = "@ id/createTable" android: text = "insert data"/> <Button android: id = "@ + id/select" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_below = "@ id/insert" android: text = ""/> <Button android: id = "@ + id/update" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_below = "@ id/select" android: text = "update data"/> <Button android: id = "@ + id/delete" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_below = "@ id/update" android: text = "delete data"/> </RelativeLayout>

Running result