It returns Cursor object so Cursor is a result-set with queried data, it provides different functions really helpful while reading data.įollowing are some overloaded query functions: query() method is overloaded with different set of parameters. SQLiteDatabase class provides query() method to read data from table. Read(select):Reading from a database table is bit different from other functions like insert,update and delete. Important Note: If you want to remove all rows and require count of deleted ones also then pass 1 as whereClause.
delete function will return number of affected row if whereClause passed otherwise will return 0. Here whereClause is optional, passing null will delete all rows in table. Public class SqliteManager extends SQLiteOpenHelper ĭb.delete( "Items", whereClause, whereArgs) Whenever we need to create a database we have to extend SQLiteOpenHelper class as follows: /**A helper class to perform database related queries*/
SQLiteOpenHelper is an abstract class with two abstract methods onCreate(SQLiteDatabase db) and onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) and many more database helpful functions. One writing raw queries and another is using parameterized functions or we can say parametrized queries.Ĭreate: Creating a database is very simple in android by using SQLiteOpenHelper class. While using SQLite there could be two different ways to perform different operations like create, read, update and delete. Android os has its own implementation to perform CRUD (Create, Read, Update, Delete)operations, so Android provides set of classes available in android.database and packages. SQLite is a structure query base database, hence we can say it’s a relation database. Android provides different ways to store data locally so using SQLite is one the way to store data.
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