Using Native SQL, you can
• Transfer values from ABAP fields to the database
• Read data from the database and process it in ABAP programs.
Native SQL works without the administrative data about database tables stored in the ABAP Dictionary. Consequently, it cannot perform all of the consistency checks used in Open SQL.
This places a larger degree of responsibility on application developers to work with ABAP fields of the correct type. You should always ensure that the ABAP data type and the type of the database column are identical.
If the database table is not defined in the ABAP Dictionary, you cannot refer directly to its data type. In this case, you should create a uniform type description in the ABAP Dictionary, which can then be used by all application programs.
If the table is defined in the ABAP Dictionary, you should remember that the sequence of fields in the ABAP Dictionary definition may not be the same as the actual sequence of fields in the
Native SQL
database. Using the asterisk (*) in the SELECT clause to read all columns into a corresponding work area would lead to meaningless results. In the worst case, it would cause an error.
The Native SQL module of the database interface passes a description of the type, size, and memory location of the ABAP fields used to the database system. The relevant database system operations are usually used to access and convert the data. You can find details of these
operations in the manuals for the programming interface of the relevant database system. In some cases, Native SQL also performs other compatibility checks.
The documentation from the various database manufacturers provides detailed lists of
combinations of ABAP data types and database column types, both for storing ABAP field values in database tables (INSERT, UPDATE) and for reading database contents into ABAP fields (SELECT). You can also apply these descriptions for the input and output parameters of
database procedures. Any combinations not listed there are undefined, and should not be used.
The following sections provide details of the data types and conversions for individual databases.
Although they are database-specific, there are also some common features.
Recommended type combinations are underlined. Only for these combinations is behavior guaranteed from release to release. For any other combinations, you should assume that the description only applies to the specified release.
The results of conversions are listed in a results column:
• “OK”: The conversion can be performed without loss of data.
• Operations that fail are indicated by their SQL error code. Errors of this kind always lead to program termination and an ABAP short dump.
• In some cases, data is transferred without an SQL error occurring. However, the data is truncated, rounded, or otherwise unusable:
− [rtrunc] Right truncation.
“Left” or “right” applies to the normal way of writing a value. So, for example, if a number is truncated, its decimal places are affected.
− [ltrunc]: Left truncation
− [round]: Number is rounded up or down during conversion
− [0]: A number that was “too small” is rounded to 0 (underflow)
− [undef]: The conversion result is undefined.
There are several possible results. The concrete result is either not known at all, or can only be described using a set of rules that is too complicated for practical use.
− [null]: The conversion returns the SQL value NULL.
− [ok]: The conversion is performed without fields and unchecked.
The original data is converted, but without its format being checked. The result may therefore be a value invalid for the result type, which cannot be processed further. An example of this is a date field containing the value “99999999” or “abcdefgh” after conversion.
Combinations of ABAP data type and database column type can be divided into finer subcategories. Here, for example, using the transfer direction ABAP → database (INSERT, UPDATE):
• If the width of the ABAP field is greater than that of the database column, the ABAP field may contain values for which there is not enough space in the database column. This can
produce other cases: The concrete data value in ABAP finds space in the database column, or not.
• If the ABAP field is at most as long as the database column, there is always space for the ABAP value in the database column.
• Some types, such as numeric columns, expect values in a particular format. This is
particularly important in connection with character types, for example, when you want to write an ABAP character field (type C) into an integer column.
Native SQL for Oracle [Page 1166]
Native SQL for Informix [Page 1184]
Native SQL for DB2 Common Server [Page 1199]