Both TurboIMAGE and ALLBASE/SQL have data types that do not map exactly to a type in the other system. But a satisfactory mapping with appropriate conversions can easily be done for most TurboIMAGE data types.
Basic Mapping |
 |
Table 5-1 shows the mapping of the most common data types from TurboIMAGE to ALLBASE/SQL:
Table 7-1 Mapping of TurboIMAGE and ALLBASE/SQL Data Types
| TurboIMAGE Data Type | ALLBASE/SQL Data Type | Description |
|---|
| I,J | SMALLINT | 16-bit integer |
| I2,J2 | INTEGER | 32-bit integer |
| K1,K2 | INTEGER | Requires conversion from binary to integer |
| Pn | DECIMAL(n-1,0) | Packed decimal |
| R4 | FLOAT | Conversion from HP 3000 real to IEEE real |
| U(n), X(n) | CHAR(n) | Byte character string |
| Zn | DECIMAL(n,0) | Requires conversion from zoned decimal to packed decimal
|
Compound Items |
|
TurboIMAGE compound items are not compatible with ALLBASE/SQL data types, because ALLBASE/SQL does not accomodate arrays. In ALLBASE/SQL, you need to create a separate column description for each member of the compound.
Null Handling |
|
TurboIMAGE does not support null values. Thus, a null value is often represented as an empty string or as zero (for numeric values).
In ALLBASE/SQL, a special data type NULL can be used to indicate the absence of a value; NULL is distinct from 0 or from an empty string, which are like any other values. If columns are not permitted to contain nulls in ALLBASE/SQL, you must define the column as NOT NULL when you create the table.
