The Synon data model explicitly declares relationships between files, and files and fields. These statements are known as Data Relations. There are Nine Data Relations in the Synon/2E product. We will focus our attention on All of those relations at this time.The Data Relations we will use are the Defined As, Known By, Has, Owned By , Refers To, Extended By ,Denoted by , Includes ,Qualified By.
1. Defined As - The Defined As data relation declares or defines a file to the Synon Data Model. When ever you enter data relations into a file the Defined As relation is a relation you need not remember to enter, it Created automatically. As compaired to other Synon Data Relations, the Defined As relation does not appear on the screen. We have to requesting that to appear . To see Defined As relations, position the cursor in one of the selection or position field called Relation Level (Rel lvl) and enter "ALL" or "DFN" and Press ENTER. All files currently defined in the data
model will be displayed.
NOTE:
If any file is deleted from the model make sure to you delete Defined as relation after deleting Functions,fields, Access Paths and in last Defined as Relation.
2. Known By - The Known By relation defines a field as a key field in a file. It is usually a Primary Key field. This is a File-to-Field relation.
3. Has - The Has relation defines a field as a non-key or data attribute field in a file. This is a File-to-Field relation.
4. Owned By - The Owned By relation causes the key fields of the owning file to be included among the key entries of the owned file as major keys. For example, if the Employee file is owned by the Company file, then the key field(s) of the Company file would be included as keys on the Employee file. The key fields of the Company file will appear before the key fields of the Employee file, making them the major keys. This is a File-to- File relation.
5. Refers To - The Refers To relation causes the key fields of the referenced file to be included as non-key fields on the referring file. For example, if the Employee file Refers To Job Master file, the keys of Job Master file will be included as non-key fields on the Employee file. This is a File-to-File relation.
6. Denoted by - The 'Denoted by' relation specifies that A CA 2E file may be defined by a special unique identifier: 'a surrogate'. A surrogate is a system wide number (of a specified size) that uniquely identifies each record in the system. For instance you might use a surrogate in an application where the normal identifiers are subject to repeated change (in effect a customer number is a limited application of this idea).
7. Extended by - The 'Extended by' relation declares A CA 2E file to be an extension of another CA 2E file. The relation records an association that is not expressed by any other relation, and in partic-ular, a one-to-one association between the identifiers of two files.
1. Defined As - The Defined As data relation declares or defines a file to the Synon Data Model. When ever you enter data relations into a file the Defined As relation is a relation you need not remember to enter, it Created automatically. As compaired to other Synon Data Relations, the Defined As relation does not appear on the screen. We have to requesting that to appear . To see Defined As relations, position the cursor in one of the selection or position field called Relation Level (Rel lvl) and enter "ALL" or "DFN" and Press ENTER. All files currently defined in the data
model will be displayed.
NOTE:
If any file is deleted from the model make sure to you delete Defined as relation after deleting Functions,fields, Access Paths and in last Defined as Relation.
2. Known By - The Known By relation defines a field as a key field in a file. It is usually a Primary Key field. This is a File-to-Field relation.
3. Has - The Has relation defines a field as a non-key or data attribute field in a file. This is a File-to-Field relation.
4. Owned By - The Owned By relation causes the key fields of the owning file to be included among the key entries of the owned file as major keys. For example, if the Employee file is owned by the Company file, then the key field(s) of the Company file would be included as keys on the Employee file. The key fields of the Company file will appear before the key fields of the Employee file, making them the major keys. This is a File-to- File relation.
5. Refers To - The Refers To relation causes the key fields of the referenced file to be included as non-key fields on the referring file. For example, if the Employee file Refers To Job Master file, the keys of Job Master file will be included as non-key fields on the Employee file. This is a File-to-File relation.
6. Denoted by - The 'Denoted by' relation specifies that A CA 2E file may be defined by a special unique identifier: 'a surrogate'. A surrogate is a system wide number (of a specified size) that uniquely identifies each record in the system. For instance you might use a surrogate in an application where the normal identifiers are subject to repeated change (in effect a customer number is a limited application of this idea).
7. Extended by - The 'Extended by' relation declares A CA 2E file to be an extension of another CA 2E file. The relation records an association that is not expressed by any other relation, and in partic-ular, a one-to-one association between the identifiers of two files.
8. Includes - The includes is used for Audit fields (eg : Date , Time ,User name , Change Date etc) It is File-To- File Relation. We Just include the file and all Audits Fields Will be available in parent file.
9. Qualified By - This relation is used on the KEY field only. It is a File-To- Field relation,For Example, in a file we need to search for the value. which exactly is not present and we are not sure about the value is there or not , In that case it will return a previous or immediate after present value
as per given *Previous or * Next by user.
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