Chapter 8 O/R Mapping Modeling
You can transform an attribute into a column. To do so you must select the Persistent option in the Detail tab of the attribute property sheet.
Persistent attributes can have simple data types or complex data types.
The simple data type is based on standard data types, such as int, float, String, Date etc. Each persistent attribute is transformed into one column. Its data type is converted into an internal standard data type. The internal standard data type is then mapped to a specific data type of the physical database.
The following table list the correspondence between simple data types supported Java and internal standard data types.
| Java data type | Standard data type | Description |
|---|---|---|
| String | VA254 | Variable character with 254 max length |
| Date | DT | Date time |
| Object | ANY | Default data type |
| Boolean | BL | Two opposing values (true/false; yes/no; 1/0) |
| Integer | I | 32 bit integer |
| Short | SI | 16 bit integer |
| Long | LI | 64 bit integer |
| Float | F | 32 floating point numbers |
| Double | N | Numbers with a fixed decimal point |
| Character | A1 | Character with 1 length |
| Byte | BT | 256 values |
| Number | N | Numbers with a fixed decimal point |
| StringBuffer | TXT | Character strings |
| Thread | ANY | Default data type |
| ThreadGroup | ANY | Default data type |
| Process | ANY | Default data type |
The following table list the correspondence between simple data types supported C# and internal standard data types.
| C# data type | Standard data type | Description |
|---|---|---|
| Array | ANY | Default data type |
| Boolean | BL | Two opposing values (true/false; yes/no; 1/0) |
| Byte | BT | 256 values |
| Char | TXT | Character strings |
| DateTime | DT | Date time |
| TimeSpan | T | Time |
| Decimal | DC | Decimal |
| Double | LF | 64 floating point numbers with double precision |
| Int16 | SI | 16 bit integer |
| Int32 | I | 32 bit integer |
| Int64 | LI | 64 bit integer |
| Object | ANY | Default data type |
| SByte | BT | 256 values |
| Single | F | 32 floating point numbers |
| String | VA254 | Variable character string with 254 max length |
| UInt16 | SI | 16 bit integer |
| UInt32 | I | 32 bit integer |
| UInt64 | LI | 64 bit integer |
These standard data types will be translated into data types supported by the DBMS of your PDM. You can refer to the database definition for the translation rules.
You can also customize the code of the generated data types in the Code box of the Persistent groupbox. You can also customize the code of the generated columns.
Attribute mapping will be generated for the attribute.
The complex data type is based on a classifier. The transformation depends on the persistent settings of the classifier. The classifier is generally used as a value type class. For more information, see Value type transformation.
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