Numeric data types

Informix®

Informix supports several data types to store numbers:

Table 1. Informix numeric data types
Informix data type Description
SMALLINT 16 bit signed integer
INTEGER 32 bit signed integer
BIGINT 64 bit signed integer
INT8 64 bit signed integer (replaced by BIGINT)
DECIMAL Equivalent to DECIMAL(16)
DECIMAL(p) Floating-point decimal number (max precision is 32)
DECIMAL(p,s) Fixed-point decimal number (max precision is 32)
MONEY Equivalent to DECIMAL(16,2)
MONEY(p) Equivalent to DECIMAL(p,2) (max precision is 32)
MONEY(p,s) Equivalent to DECIMAL(p,s) (max precision is 32)
REAL / SMALLFLOAT 32-bit floating point decimal (C float)
DOUBLE PRECISION / FLOAT[(n)] 64-bit floating point decimal (C double)

SAP HANA®

SAP HANA supports the following numeric data types:

Table 2. SAP HANA numeric data types
SAP HANA data type Description
SMALLINT 16 bit signed integer
INTEGER 32 bit signed integer
BIGINT 64 bit signed integer
DECIMAL(p,s) Fixed point decimal (max p is 38)
DECIMAL(p) Floating point decimal (approximative)
DECIMAL Floating point decimal (approximative)
SMALLDECIMAL Floating point decimal (approximative)
REAL 32-bit floating point decimal (C float)
FLOAT[(n)] (DOUBLE) 64-bit floating point decimal (C double)

Solution

Table 3. Informix numeric data types and SAP HANA equivalents
Informix data type SAP HANA equivalent
SMALLINT SMALLINT
INTEGER INTEGER
INT8 / BIGINT BIGINT
DECIMAL(p,s) DECIMAL(p,s)
DECIMAL(p<=19) DECIMAL(p*2,p)
DECIMAL(p>19) N/A: Max p is 38 for SAP HANA
DECIMAL DECIMAL(32,16)
MONEY DECIMAL(16,2)
MONEY(p) DECIMAL(p,2)
MONEY(p,s) DECIMAL(p,s)
SMALLFLOAT REAL
FLOAT[(n)] DOUBLE

SQL scripts to create databases must be converted manually. Tables created from BDL programs do not have to be converted; the database interface detects the MONEY data type and uses the DECIMAL type for SAP HANA.

Important: There is no SAP HANA equivalent for the Informix DECIMAL(p) floating point decimal (i.e. without a scale). If your application is using such data types, you must review the database schema in order to use SAP HANA compatible types. To workaround the SAP HANA limitation, the SAP HANA database driver converts DECIMAL(p) types to a DECIMAL( 2*p, p ), to store all possible numbers an Informix DECIMAL(p) can store. However, the original Informix precision cannot exceed 19, because SAP HANA supports a maximum DECIMAL precision of 38 (2*19). If the original precision is bigger than 19, a CREATE TABLE statement executed from a Genero program will fail with an SQL error.
The numeric types translation can be controlled with the following FGLPROFILE entries:
dbi.database.dsname.ifxemul.datatype.smallint = { true | false }
dbi.database.dsname.ifxemul.datatype.integer = { true | false }
dbi.database.dsname.ifxemul.datatype.bigint = { true | false }
dbi.database.dsname.ifxemul.datatype.int8 = { true | false }
dbi.database.dsname.ifxemul.datatype.decimal = { true | false }
dbi.database.dsname.ifxemul.datatype.money = { true | false }
dbi.database.dsname.ifxemul.datatype.float = { true | false }
dbi.database.dsname.ifxemul.datatype.smallfloat = { true | false }
For more details see IBM Informix emulation parameters in FGLPROFILE.