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Android sqlite tutorial
Android sqlite tutorial







The SQLite open helper class gives the name and version in the constructor. OnUpgrade() method is called, if the database version is updated.OnCreate() method is called, if the database does not exist.Here, two things are to be taken into account: Whenever one talks about SQLite open helper class, its database name & version gets passed in the constructor of extended class. Also, it must be noted that whenever one increases the DB version, it will automatically call onUpgrade on to it. These methods are automatically handled or called by the framework. Also it is recommended to perform database synchronously. It is always preferred to make sure that the least impact or queries running in recursion are avoided when an SQL query is executed.

android sqlite tutorial android sqlite tutorial

When the SQLite database is accessed, it can be slow sometimes, depending on the complexity of the query. Thereby there is no dependency at allĬoming back, when we extend SQLiteopenHelper class, we overwrite the Oncreate & OnUpgrade methods in this class. There is no change in the SQLite version of the object since one handling creation/update of database, and the other is playing on data held into the tables of the database. User Questions:ĭoes the change in db version result is change of SQLite version of the object? Note: The SQLiteOpen Helper class is used to manage database creation and version management. *One can find the database by clicking on package and accessing the data folder to the database folder, which contains the file. The end result is a test table with an invalid datatype, which shows that SQLite doesn’t validate datatype. A random value datatype has been created. Here, a new table is added with ‘text’ in the name field and fieldname box carrying ‘textfield’. In other words, whatever datatypes are used, they are termed as valid.įor example, in this case, the database of a cable operator has been discussed. Real(like double)- for storing long valuesīasically SQLite does not validate datatypes by itself.

android sqlite tutorial

Integer(like int) – for storing integer primary key.Text(like string) – for storing data type store.Once SQLite is in place, it is important to ensure that a feature or command is available in SQLite only then can it be executed. It supports standard relations database features, like SQL syntax, transactions & SQL statements. SQLite is considerably, the lighter version of SQL database, where most of the SQL commands don’t run on SQLite database.

android sqlite tutorial

SQLite is an open source database, available on every android database. Every device has an inbuilt support for SQLite database, which is automatically managed on android right from its creation, execution to querying up process. The Android SQLite Database requires very little memory (around 250kb), which is available on all android devices.









Android sqlite tutorial