What is declare expression in PEGA

Declare Expression is one among the four main types of declarative rules in Pega which target a single property either to obtain its value or to validate the value.

What is declarative rule?

Declarative Processing: Automatic calling and execution of rules by process commander. We create declarative rule and leave them without referring from any other rule. These rules gets auto executed when we used the properties which are involved in declarative rules.

What is backward chaining in PEGA?

Backward chaining executes declare expression rules when a value is needed for a property, as opposed to when inputs change. For example, a value may be needed because a property’s value is referenced in an HTML stream for display.

What is forward chaining and backward chaining in PEGA?

Forward chaining is executed when the value of any of the source properties change. Backward Chaining mode executes when the target property is referenced. Backward chaining is supported only for declare expressions. … For your example i.e. A=B+C, we need to use forward chaining.

What is declare constraints in PEGA?

Declare Constrain is a declarative processing which automatically run validation when a specified property is touched.

What is an example of backward chaining?

Use backward chaining (i.e., breaking a skill down into smaller steps, then teaching and reinforcing the last step in the sequence first, then the second to the last step, and so on). For example, have the child wash his/her hands in the sink near the toilet.

What is decision rule in PEGA?

A decision rule is usually called from a flow and is used to make a decision about the path the flow should take. It can also be called from a declarative rule. A Decision table contains one or more rows, each containing test conditions and a result to return.

What is edit validate in PEGA?

A validate rule confirms the data entered meets certain specified conditions, and are only ever used w/ user input. An edit validate rule confirms the data entered is in the correct format, and are only ever used on a property rule.

What is trigger in PEGA?

Create Declare Trigger rules to cause an activity to run when instances of a specific class are created, updated, or deleted in the database. … For each Declare Trigger rule, the Pega Platform monitors database operations for objects of the Applies To class (and concrete classes derived from that class).

What are constraints in databases?

Constraints are the rules enforced on the data columns of a table. These are used to limit the type of data that can go into a table. This ensures the accuracy and reliability of the data in the database. … PRIMARY Key − Uniquely identifies each row/record in a database table.

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What is PEGA validation?

1) What is a Validate rule? Ensures that a valid data is entered in form or validates data received from other system. When a field fails validation, the rule adds an error message and prevents successful submission of form. We can add validation for any property rule and we can customize the error message.

What is clipboard in PEGA?

Pega Platform™ provides the Clipboard tool to display data in memory. The Clipboard tool organizes and presents all the pages in memory, listing all the properties on each page and the value of each property.

What is PEGA fork?

For a Fork shape, the tests are on the connectors themselves; the tests return true or false. Connector tests are evaluated one by one, based on the likelihood percentages. … Fork Shape : It is like multiple concurrent tasks, it evaluates one by one based on the likelyhood percentages.

What is MAP value in PEGA?

This rules allows tow properties, one for ROW and the other for COLUMN. This rule requires minimum, one property in the logic and Maximum two properties. If more than two properties we need to use other decision rules, we cannot use map value. The result of map value can be, a calculated value of Row and Column.

What are the three types of chaining?

There are three different types of chaining which can be used and they are forward chaining, backward chaining, and total task chaining (not to be confused with a task analysis).

What is shaping and chaining?

Shaping and Chaining. Shaping involves reinforcing successive approximations of a desired behaviour. It is widely used by animal trainers to teach the animals to perform tricks. Chaining involves one response leading to the occurance of another response. Most behaviours occur in chains.

What is total task chaining?

Total task chaining: occurs when the entire skill is taught, and the learner is given support for only challenging steps. For example, if it was challenging for your child to turn on the tap and get soap, but they were able to do the other steps, these specific steps would be taught using a prompt fading system.

What is declare on change?

A Declare OnChange rule automatically executes an activity, or suspends the current work object, when the value of a specified property changes.

What is the difference between declare OnChange and declare trigger?

The primary difference between these two are Declare triggers listen to persistence events like (Save/Delete), while Declare On change listens to any property update in a clipboard.

How do you declare a trigger?

1. CREATE [OR REPLACE] TRIGGER trigger_name − Creates or replaces an existing trigger with the trigger_name.
2. {BEFORE | AFTER | INSTEAD OF} − This specifies when the trigger will be executed. …
3. {INSERT [OR] | UPDATE [OR] | DELETE} − This specifies the DML operation.

What is Obj list view in PEGA?

The Obj-List-View method uses information in the Content tab and Display Fields tab of a list view rule to determine which instances to retrieve, and which columns of those instances to place on the embedded pages of a Code-Pega-List page. Information on other tabs of the List View form is ignored.

What does PK mean in database?

Primary Key Constraints A table typically has a column or combination of columns that contain values that uniquely identify each row in the table. This column, or columns, is called the primary key (PK) of the table and enforces the entity integrity of the table.

What is integrity in Rdbms?

Data integrity is the overall completeness, accuracy and consistency of data. This can be indicated by the absence of alteration between two instances or between two updates of a data record, meaning data is intact and unchanged.

What is schema in Rdbms?

In a relational database, the schema defines the tables, fields, relationships, views, indexes, packages, procedures, functions, queues, triggers, types, sequences, materialized views, synonyms, database links, directories, XML schemas, and other elements. A database generally stores its schema in a data dictionary.

What are the debugging tools in PEGA?

1 Answer. There are two built-in tools that will help you with debugging: Tracer and Clipboard. The former shows you which rules are involved, the order in which they are called, and data passed in/modified by certain rules, as well as the entire stack to help you track down any error.

What is a thread in PEGA?

Thread – the page is created in a single requestor thread, and can be accessed as often as needed by processing in that thread. Access by separate requestors causes the rule to create distinct pages, which might have different contents. Requestor – all threads for the current requestor.

What are data pages in PEGA?

In Pega Platform™ applications, a data page retrieves data from a specified data source and caches that data in memory. A data page manages the integration to the data source, separating business processes from any integration details.

What is code page list in PEGA?

Code-Pega-List is a core class for Pega Platform. Many rules used it, such as methods in activity rule ( Obj-Browse ), report definition rule, etc. This class contains standard logic, for example count of elements in page-list contain in property . pxResults .

What is flow shapes in PEGA?

A shape in a flow represents a task that a user or application completes as part of a business process. By connecting different types of shapes in a flow, you can define the path that a case follows from creation to resolution.

What is split join in PEGA?

Split Join : You want to start multiple flows ex. BackgroundCheck, EmploymentCheck etc. This is not based on a Page list, you need to specify all Flows to start in configuration. Another Example : Work item needs approval from two different teams to continue further.

What are different types of flows in PEGA?

There are two types of flow actions: Connector — Completes the current assignment and advances the flow to the next shape in the sequence. Connector flow actions are configured on the line shapes, or connectors, in a flow that exit assignment shapes.