SAP HANA character string types

CHAR/VARCHAR/TEXT SQL type names can be converted to ASCII-7 or national character types, with an FGLPROFILE entry.

Before Genero BDL version 4.00, when creating a table in a program using CHAR, VARCHAR or TEXT column types, these SQL types names were converted to SAP HANA national character types (assuming that the application wants to store ISO-8859-? or UTF-8 data).

There was no option to force VARCHAR/CLOB SQL types, when only pure English ASCII-7 data needs to be stored.

Note:

In fact, SAP HANA database tables could be directly created with the required native SQL types, by using SAP HANA SQL command tools. This is about creating tables from Genero programs.

Table 1. SQL type conversions in versions before version 4.00
SQL type in .4gl SQL	Native SQL type
`CHAR(n)`	NVARCHAR(n) (SAP HANA has no CHAR!)
VARCHAR(n)	NVARCHAR(n)
TEXT	NCLOB

Starting with version 4.00, you can control CHAR/VARCHAR/TEXT SQL type name conversion with the dbi.database.dbname.ifxemul.nationalchars FGLPROFILE entry.

For pure English applications, use VARCHAR/CLOB SQL columns in SAP HANA to store ASCII-7 data. For ISO-8859-? or UTF-8 applications, use NVARCHAR/NCLOB SQL types.

Important:

The dbi.database.dbname.ifxemul.nationalchars FGLPROFILE entry is by default false and needs to be set to true, if your application uses ISO-8859-? or UTF-8 character sets.

Table 2. SQL type conbersions since version 4.00
SQL type in .4gl SQL	Native SQL type when`ifxemul.nationalchars=false` (default)	Native SQL type when`ifxemul.nationalchars=true`
`CHAR(n)`	VARCHAR(n) (SAP HANA has no CHAR!)	NVARCHAR(n)
VARCHAR(n)	VARCHAR(n)	NVARCHAR(n)
TEXT	CLOB	NCLOB

Note also that in version 4.00, the fgldbsch schema extraction tool does the following conversions from the native SQL types to FGL types to produce .sch files:

Table 3. fgldbsch schema extraction rules since verison 4.00
Native SQL type	Conversion mode A	Conversion mode B
`CHAR(n)`	CHAR(n)	CHAR(n)
VARCHAR(n)	VARCHAR2(n)	VARCHAR2(n) (was `CHAR(n)` in prior versions)
NCHAR	CHAR(n)	NCHAR(n)
`NVARCHAR(n)`	VARCHAR2(n)	NVARCHAR2(n)
CLOB	TEXT	TEXT
NCLOB	TEXT	TEXT

For more details, see CHAR and VARCHAR data types, TEXT and BYTE (LOB) types and ifxemul FGLPROFILE settings.