Tasks (Magic xpa 4.x)
A task is the basic object to construct programs to implement procedures that make up the project.
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There is a difference between a task and a program. A task is the basic unit for constructing a program. A program can be constructed of a main task and subtasks.
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Because almost every database procedure requires some variation of looping through a database table, the engine executes a task by looping through a data source called the Main Source of the task.
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You define a task’s Main Source in the first line of the Data View Editor, selecting either one of the data sources you previously defined in the project’s Data repository, or 0 for no Main Source.
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In the Task Properties dialog box, set the Task type property to Online, Rich Client, Batch, Browser, or Web Client.
In an Online, interactive Rich Client, Web Client, or Browser task, the end user browses the Main Source by moving from record to record. This means that the only records processed are those browsed by the end user. This is useful if your program needs to interact with the end user.
In a Batch or non-interactive Rich Client task, Magic xpa loops automatically through the data source. It simply starts with the first record in the data view you define and visits every record until it reaches the last record. This is useful if your program has to perform automatic procedures, such as generating reports and global table updates.
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Once you have specified the Main Source and the task type, you can then customize the task to accomplish a specific job. You tell Magic xpa what actions, to perform and according to which rules, at each stage of the loop: task, record, control, or group for Batch tasks.
Engine Execution Levels
Browser Client Applications
Rich Internet Applications
User-Defined Events
User-Defined Functions
Task Data View
Mode of Operations on the Task Flow
Multi-Threading
