Package | flash.data |
Class | public class SQLResult |
Inheritance | SQLResult Object |
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 |
The SQLResult instance for a SQL statement is accessed by calling the
SQLStatement.getResult()
method or
as an argument passed to the result handler of a Responder instance specified in a call to
SQLStatement.execute()
or SQLStatement.next()
. Generally, developer
code does not construct SQLResult instances directly.
You use a SQLResult object to access the rows of data returned from a
SELECT
statement (using the data
property), to get
row identifier information for an INSERT
statement (using the
lastInsertRowID
property), to determine the number of rows affected
by an INSERT
, UPDATE
, or DELETE
statement
(using the rowsAffected
property), or to determine whether there are
additional SELECT
result rows that haven't been retrieved (using the
complete
property).
More examples
Related API Elements
Property | Defined By | ||
---|---|---|---|
complete : Boolean [read-only]
Indicates whether all the resulting data from a statement execution has been returned. | SQLResult | ||
constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | ||
data : Array [read-only]
The data returned as a result of the statement execution, specifically when
a SQL SELECT statement is executed. | SQLResult | ||
lastInsertRowID : Number [read-only]
The last generated row identifier generated by a SQL INSERT
statement. | SQLResult | ||
rowsAffected : Number [read-only]
Indicates how many rows were affected by the operation. | SQLResult |
Method | Defined By | ||
---|---|---|---|
Creates a SQLResult instance. | SQLResult | ||
Indicates whether an object has a specified property defined. | Object | ||
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | ||
Indicates whether the specified property exists and is enumerable. | Object | ||
Sets the availability of a dynamic property for loop operations. | Object | ||
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | ||
Returns the string representation of the specified object. | Object | ||
Returns the primitive value of the specified object. | Object |
complete | property |
complete:Boolean
[read-only] Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 |
Indicates whether all the resulting data from a statement execution has been returned.
When a statement returns one or more rows this property indicates
whether all of the rows have been returned. When a SQLStatement object's execute()
method is called with a prefetch
argument value, only the specified number of
rows of the resulting
data are returned in the SQLResult object's data
property. Subsequent calls
to SQLStatement.next()
cause additional data to become available. This property
is used to determine when the final results have been returned.
Note that because the number of rows is unknown at execution time, the database cursor must move beyond
the last row before a statement's execution is considered complete. When the
SQLStatement.execute()
method is called with a prefetch
argument, at least one
row more than the total number of rows in the result set must be requested before
the resulting SQLResult instance's complete
property is true
.
Implementation
public function get complete():Boolean
Related API Elements
data | property |
data:Array
[read-only] Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 |
The data returned as a result of the statement execution, specifically when
a SQL SELECT
statement is executed.
When a statement returns one or more rows this property is an array containing objects that represent the rows of result data. Each object in the array has property names that correspond to the result data set's column names.
For example, suppose you execute the following SQL SELECT
statement:
SELECT lastName, firstName FROM employees
Assuming the employees
table contains 10 rows, the
SQLResult.data
property is an Array with 10 elements. Each element
is an object with two properties, lastName
and firstName
.
The situation is more complex when you are using a SELECT
statement
with a complex result column, such as an aggregate function. For example,
suppose you execute the following SQL:
SELECT departmentId, SUM(salary) FROM employees GROUP BY departmentId
In the results from this statement, each object in the data
Array has
two properties named departmentId
and SUM(salary)
. However,
"SUM(salary)" is not a valid identifier. If you are using a computed column such as an
aggregate or other function, specify an alias for the computed column in your SQL
statement. The alias is used as the property name in the result data objects. For
example, consider this alternative to the previous statement:
SELECT departmentId, SUM(salary) AS salarySubtotal FROM employees GROUP BY departmentId
In this statement's data
array, the result objects have two
properties named departmentId
and salarySubtotal
.
The data
property is always an Array regardless of how many rows
and columns are in the result set. For example, the following SELECT
statement
results in one row and one column, which is essentially a single value:
SELECT COUNT(*) AS numEmployees FROM employees
After executing the query the data
property contains an Array object
with one element. That element is an object with a single property,
numEmployees
.
If there are duplicate column names in the result data, for example if the
SELECT
statement includes an two different id
columns
from two different tables, the duplicate names are given property names according
to the value of the SQLConnection.columnNameStyle
property. By default,
each column's name is used as the property name, but if there is are multiple columns
in the result set with the same name, the long name format
[table-name]_[column-name]
is used for the identically named columns.
This behavior can be changed by setting the SQLConnection.columnNameStyle
property.
By default the objects in the data
Array are Object instances.
However, by setting the value of the SQLStatement.itemClass
property
to a class, the data
Array elements are created as instances of
that class instead. For every column in the result data set, the
itemClass
class must have a property whose name exactly matches the
column name.
If a statement does not return any data this property is null
.
This is the case if the statement is not a SELECT
statement, or if
it is a SELECT
statement that returns 0 rows.
Implementation
public function get data():Array
Related API Elements
Example ( How to use this example )
itemClass
property
to have the runtime create instances of a custom class from SQL SELECT
statement
results.
// Employee class definition package { public class Employee { public var name:String; public var ssn:String; public var id:uint; public override function toString():String { return "id: "+ id.toString() + " name: " + name + " ssn: " + ssn; } } } // using the Employee class as SQLStatement.itemClass var conn:SQLConnection; var dbStatement:SQLStatement; function init():void { conn = new SQLConnection(); conn.addEventListener(SQLEvent.OPEN, connOpenHandler); dbStatement = new SQLStatement(); dbStatement.sqlConnection = conn; dbStatement.text = "SELECT id, name, ssn FROM employees"; dbStatement.itemClass = Employee; var dbFile:File = new File(File.separator + "employee.db"); conn.open(dbFile); } function connOpenHandler(event:SQLEvent):void { dbStatement.addEventListener(SQLEvent.RESULT, resultHandler); dbStatement.execute(); } function resultHandler(event:SQLEvent):void { var result:SQLResult = dbStatement.getResult(); if (result != null) { var emp:Employee; var numRows:int = result.data.length; for (var i:int = 0; i < numRows; i++) { emp = result.data[i]; trace(emp.toString()); } } }
lastInsertRowID | property |
lastInsertRowID:Number
[read-only] Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 |
The last generated row identifier generated by a SQL INSERT
statement.
The value is 0 if the executed statement was not an
INSERT
statement.
A row identifier is used to uniquely identify a row in a table within the database. The value is frequently generated by the database.
For more information about primary keys and generated row identifiers, see the "CREATE TABLE" and "Expressions" sections in the appendix "SQL support in local databases."
Implementation
public function get lastInsertRowID():Number
More examples
Related API Elements
rowsAffected | property |
rowsAffected:Number
[read-only] Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 |
Indicates how many rows were affected by the operation.
Only changes that are directly specified by an INSERT
,
UPDATE
, or DELETE
statement are counted.
Auxiliary changes caused by triggers are not counted.
Use the SQLConnection.totalChanges
property to find the total
number of changes including changes caused by triggers.
Note that when the related SQL operation is a DELETE
statement
with no WHERE
clause (that is, the statement deletes all the rows in the table),
the rowsAffected
property is always 0, regardless of the number of rows
that were deleted. If you need to know the number of rows that are deleted, you can
include the WHERE
clause WHERE 1 = 1
, in which case all
the rows are deleted, and the rowsAffected
property accurately
reflects the number of rows that were deleted. However, depending on the number of
rows being deleted, doing so may have a negative impact on the statement's performance.
Implementation
public function get rowsAffected():Number
Related API Elements
SQLResult | () | Constructor |
public function SQLResult(data:Array = null, rowsAffected:Number = 0, complete:Boolean = true, rowID:Number = 0)
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 |
Creates a SQLResult instance. Generally, developer code does not call the SQLResult
constructor directly. To retrieve a SQLResult instance associated with a particular SQLStatement
instance, call the instance's getResult()
method. A SQLResult
instance is also passed as an argument to the result handler function when
a Responder instance is specified for an execute()
or next()
method call.
data:Array (default = null ) — The array of rows returned from the execution of a statement. If
the statement doesn't return any rows this value should be null.
| |
rowsAffected:Number (default = 0 ) — Indicates how many rows the executed statement affected.
| |
complete:Boolean (default = true ) — Indicates whether there are additional rows that can
be fetched or whether all data has been returned.
| |
rowID:Number (default = 0 ) — If the statement was a SQL INSERT operation this is the new
unique identifier for the row.
|
Wed Nov 21 2018, 06:34 AM -08:00