Cache for UNIX 2018.1.2
This class has been superseded. It will remain for compatibility with existing code and samples.
We recommend using
Cached ResultSet based on an SQL statement. This class only supports the SELECT statement.
Clone the current object to a new object. If deep is 1 then this does a deep copy which will also copy any subobjects and if deep is 0 then it will create another reference to any subobjects and increment the reference count appropriately. It returns the new cloned object.
Note that even if deep=0 when you clone a parent object in a parent child relationship or a one object of a one to many relationship then it will construct clones of all the child/many objects. This is because a child/many object can only point at a single parent and so if we did not create a clone of these then you would have a relationship with zero items in it. If you really just want to clone the object without these child/many objects then pass deep=-1 to this method.
After the clone is constructed it will call %OnConstructClone(object,deep,.cloned) on the clone if it is defined so that you can perform any additional steps e.g. taking out a lock. This works just the same way as %OnNew() does.
The object is the oref of the original object that was cloned. The cloned array is just used internally when doing a deep clone to prevent recursive loops, do not pass anything in at all for this parameter on the initial call. If you write a %OnConstructClone and from here you wish to call %ConstructClone on another object pass in the cloned array, e.g. 'Do oref.%ConstructClone(1,.cloned)' so that it can prevent recursive loops.
The location is used internally to pass the new location for stream objects.
Normalizes all of an object's property values by invoking the data type Normalize methods. Many data types may allow many different representations of the same value. Normalization converts a value to its cannonical, or normalized, form.
%Prepare() This method is different for each type of result set class. This method has two tasks. First, instantiate the correct concrete result set class. For %ResultSet.SQL that means accepting the sql query text in the first parameter and looking up the query implementation in the query cache. The second task is to prepare the resulting object for data retrieval by the caller which is done in %OnNew. The assumption is that if the query requires any parameters then the actual arguments are all literal or public variables.
For %ResultSet.SQL, the arguments are:
sqlStatement (byref) the SQL Select statement, either as a counted array or as a $$$NL delimited string; returnError (byref) if an error occurs, this will be an oref of an instance of %SYSTEM.Error. That object has a Status property as well as methods to convert that status value into message id's and text from other error domains. If no error is detected during %Prepare then returnError is $$$NULLOREF; %importPackages this is a $list of package names to be used to resolve any unqualified names in the SELECT statement.
For example, SELECT %ID from MyTable
If %importPackages contains "Sample" then the schema associated with the Sample package would be used to qualify MyTable.
%args... variable number of argument values that correspond to '?' parameters contained in the sqlStatement.
This method returns an instance of %Library.IResultSet in the generic case. In the case of %ResultSet.SQL, an instance of %ResultSet.SQL is returned.
This method constructs a SaveSet containing objects that are part of the current %Save() for persistent classes or %GetSwizzleObject for serial classes. A queue of objects to be saved or serialized is also constructed. Only modified objects are included in the save queue. The value (OID or serial value in OID form) of each object is also placed in the SaveSet.
%PrepareMetaData is similar to %Prepare except that no result set is instantiated. This method returns a %ResultSet.MetaData object. Be aware that the implementation of this method might cause the result set to be instantiated but that is up to the result set class itself and no result set is actually returned by this method - only metadata.
query This is the SQL SELECT statement returnError If an error occurs this is returned by reference and is a %SYSTEM.Error object with properties set to describe information about the error. %returnError.Status contains the %Status value. importPackages This is a comma delimited list of packages to import. This is only relevant if the result set implementation is generated and the query source might include unqualified names. The import packages list is used to resolve package/schema names for unqualified names.
This method retrieves all of the serial values for referenced objects and places them into the instance variables, Validates, Normalizes, and serializes the object (with a save of the persistent image if persistent).
This method is not meant to be called directly. It is called by %Save and by %GetSwizzleObject.
This method validates an object. The %Save method of a persistent class calls it before filing any objects in the database. The %ValidateObject method of a referencing object can call it. You can also call it explicitly at any time.
%ValidateObjectdoes the following:
- It tests if any required property values are missing.
- If the PROPERTYVALIDATION class parameter is set to ValidateOnSave, it validates each non-null property value by calling the property method IsValid on each literal property and the object's %ValidateObject method for object-valued properties.
- If present, it will call a user-supplied
If any of these tests fail,
%ValidateObjectimmediately returns an error value. It is up to the caller of %ValidateObject to process the error value.
%Statusvalue indicating success or failure.