HP 3000 Manuals HP 3000 Manuals
Mapping of Data Types
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 5-1. Mapping of TurboIMAGE and ALLBASE/SQL Data Types
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| | | |
| TurboIMAGE | ALLBASE/SQL | Description |
| Data Type | Data Type | |
| | | |
----------------------------------------------------------------------------------------------
| | | |
| I,J | SMALLINT | 16-bit integer |
| | | |
----------------------------------------------------------------------------------------------
| | | |
| I2,J2 | INTEGER | 32-bit integer |
| | | |
----------------------------------------------------------------------------------------------
| | | |
| K1,K2 | INTEGER | Requires conversion from |
| | | binary to integer |
| | | |
----------------------------------------------------------------------------------------------
| | | |
| P n | DECIMAL( n-1,0) | Packed decimal |
| | | |
----------------------------------------------------------------------------------------------
| | | |
| R4 | FLOAT | Conversion from HP 3000 real |
| | | to IEEE real |
| | | |
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| | | |
| U( n), X( n) | CHAR( n) | Byte character string |
| | | |
----------------------------------------------------------------------------------------------
| | | |
| Z n | DECIMAL( n,0) | Requires conversion from |
| | | zoned decimal to packed |
| | | decimal |
| | | |
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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.