ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with local SQL databases in AIR
Using synchronous database operations
Adobe AIR 1.0 and later
There is little difference in the actual code that you use to execute and respond to operations when using synchronous
execution, compared to the code for asynchronous execution mode. The key differences between the two approaches
fall into two areas. The first is executing an operation that depends on another operation (such as SELECT result rows
or the primary key of the row added by an INSERT statement). The second area of difference is in handling errors.
Writing code for synchronous operations
Adobe AIR 1.0 and later
The key difference between synchronous and asynchronous execution is that in synchronous mode you write the code
as a single series of steps. In contrast, in asynchronous code you register event listeners and often divide operations
among listener methods. When a database is connected in synchronous execution mode, you can execute a series of
database operations in succession within a single code block. The following example demonstrates this technique:
var conn:SQLConnection = new SQLConnection();
// The database file is in the application storage directory
var folder:File = File.applicationStorageDirectory;
var dbFile:File = folder.resolvePath("DBSample.db");
// open the database
conn.open(dbFile, OpenMode.UPDATE);
// start a transaction
conn.begin();
// add the customer record to the database
var insertCustomer:SQLStatement = new SQLStatement();
insertCustomer.sqlConnection = conn;
insertCustomer.text =
"INSERT INTO customers (firstName, lastName) " +
"VALUES ('Bob', 'Jones')";
insertCustomer.execute();
var customerId:Number = insertCustomer.getResult().lastInsertRowID;
// add a related phone number record for the customer
var insertPhoneNumber:SQLStatement = new SQLStatement();
insertPhoneNumber.sqlConnection = conn;
insertPhoneNumber.text =
"INSERT INTO customerPhoneNumbers (customerId, number) " +
"VALUES (:customerId, '800-555-1234')";
insertPhoneNumber.parameters[":customerId"] = customerId;
insertPhoneNumber.execute();
// commit the transaction
conn.commit();
As you can see, you call the same methods to perform database operations whether you’re using synchronous or
asynchronous execution. The key differences between the two approaches are executing an operation that depends on
another operation and handling errors.
Last updated 6/6/2012
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