![]() So bear in mind i'm new to sqlite been working with it less than a week. I have the column name, old and new value, database name, table name etc however the issue is allowing them to update the value i've seen things like the where clause but the issue is if a column has the value multiple times (which could very well be the case) it won't know the correct row. I set it up so when a value is long pressed an edit text shows where the user can input the new value and then when okay is pressed it should update the value. if distinct is passed as true Cursor data set will not have any duplicate row.Hi i'm working on an SQLite viewer in android using java and shell commands (so commands have to be one line) i've written the layout and viewer and all everything is perfect. Most of the parameters in query overloaded functions are optional except from table and distinct any of other parameters can be passed as null. The following examples show how to use (). public Cursor query (boolean distinct, String table, String columns, String selection, String selectionArgs, String groupBy, String having, String orderBy, String limit).public Cursor query (String table, String columns, String selection, String selectionArgs, String groupBy, String having, String orderBy).For instance, imagine that an employee was supposed to enter new coffee prices in the table COFFEES but delayed doing it for a few days. In addition to grouping statements together for execution as a unit, transactions can help to preserve the integrity of the data in a table. public Cursor query (String table, String columns, String selection, String selectionArgs, String groupBy, String having, String orderBy, String limit) Using Transactions to Preserve Data Integrity.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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