![]() ![]() Insert in batches: First I inserted each row one after another, it took about 60s. PRAGMA settings: PRAGMA journal_mode = OFF I found this excellent Stack Overflow post and trying it out. Then I randomly generate these 3 values and insert them. I create a db with one table which has 3 columns. I was wondering if there are any further optimisations / tricks I can do. I have been able to insert 100M rows in 33 seconds on my local machine. I am fine with db corruptions, issues due to process crash / OS. Note that this is a parameterized SQL query, so in essence, it's a prepared statement.Hey everyone! I am very new to SQLite and I am doing a little experiment where I am trying to figure out really fast way to insert rows in SQLite. See this snippet Genscripts in case you want a more complete one. String strCountryName = c.getString(cursor.getColumnIndex("country_name")) ** Assuming that you have a field/column with the name "country_name" */ String strCountr圜ode = c.getString(cursor.getColumnIndex("code")) String columnsToReturn =, /**< Selection arguments. SQLiteDatabase db = dbHelper.getReadableDatabase() Usually you will run the query() method of SQLiteDatabase to get a cursor. Long result = statement.simpleQueryForLong() You don't run a query with it unless you only need a simple result, like the number of rows in the database, which you can do with simpleQueryForLong() String sql = "SELECT COUNT(*) FROM table_name" That's not what SQLiteStatement is for, though. Normally when you run a query, you want to get a cursor back with lots of rows. String sql = "DELETE FROM " + table_name + The executeUpdateDelete() method can also be used for DELETE statements and was introduced in API 11. Int numberOfRowsAffected = statement.executeUpdateDelete() String sql = "UPDATE table_name SET column_2=? WHERE column_1=?" You can also apply the concepts from the section above. Turbocharge your SQLite inserts on Android.Android SQLite Transaction Example with INSERT Prepared Statement.Android SQLite bulk insert and update example.Atomic Commit In SQLite (Great in depth explanation, go to Part 3).Statement.bindString(2, stringValue + i) ĭb.setTransactionSuccessful() // This commits the transaction if there were no exceptionsĬheck out these links for some more good info on transactions and speeding up database inserts. String sql = "INSERT INTO table_name (column_1, column_2) VALUES (?, ?)" Here is an example: String stringValue = "hello" This allows all the changes to be applied at once. You can speed things up even more by using transactions. The prepared statement makes it so that the SQL statement doesn't have to be parsed and compiled every time. Usually you use prepared statements when you want to quickly repeat something (like an INSERT) many times. Statement.bindString(2, stringValue) // matches second '?' in sql string Statement.bindLong(1, intValue) // 1-based: matches first '?' in sql string ![]() Of course, you wouldn't want to always enter the same things in every row. Note that the executeInsert() method is used rather than execute(). SQLiteStatement statement = db.compileStatement(sql) (But see this question.) Insert values String sql = "INSERT INTO table_name (column_1, column_2) VALUES (57, 'hello')" The execute() method does not return a value so it is appropriate to use with CREATE and DROP but not intended to be used with SELECT, INSERT, DELETE, and UPDATE because these return values. SQLiteStatement stmt = db.compileStatement(sql) (That means you wouldn't use them for most queries.) Below are some examples: Create a table String sql = "CREATE TABLE table_name (column_1 INTEGER PRIMARY KEY, column_2 TEXT)" SQLiteStatement is meant to be used with SQL statements that do not return multiple values. See this article for a general discussion on prepared statements. Prepared statements help you speed up performance (especially for statements that need to be executed multiple times) and also help avoid against injection attacks. ![]() For prepared SQLite statements in Android there is SQLiteStatement. ![]()
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