What does it do? Type adjustment in AB_SQL . A cast expression converts the value of the operand sql_exp to the dictionary type specified by dtype. SQL expressions, which have a type that matches dtype as shown below, can be used as an operand sql_exp. The result is a representation of the source value in type dtype. Built-in data types in the ABAP Dictionary with the following syntax can be specified for dtype :
Numeric types
INT1
INT2
INT4
INT8
DEC$[( len$[, decimals$] )$]
D16N for DECFLOAT16
D34N for DECFLOAT34
FLTP
Character-like types
CHAR$[( len )$]
SSTRING$[( len )$]
Byte-like types
RAW $[( len )$]
Date types/time types
DATS
TIMS
DATN
TIMN
UTCL for UTCLONG
Character-like types with special semantics
NUMC$[( len )$]
CLNT
LANG
Currency fields and quantity fields
CURR$[( len$[, decimals$] )$]
CUKY
QUAN$[( len$[, decimals$] )$]
UNIT( 2$|3 ) len and decimals can be used to specify lengths and decimal places for those dictionary types that have variable lengths and decimal places. Literals or host constants of the ABAP type b, s, i , or int8 can be specified for len and decimals. If no lengths or decimal places are specified for these types, these values are taken from the result of the specified SQL expression sql_exp. In both cases, the lengths and decimal places must meet the requirements of the following table. If the operand NULL is cast, the length of dictionary types that have a variable length must be specified. The following table shows which combinations of built-in data types in the ABAP Dictionary can currently be cast to each other and the corresponding prerequisites. There is a special list of conversion rules for every combination. from/toINT1INT2INT4 INT8DECCURRQUANDECFLOAT16DECFLOAT34 FLTPCHARSSTRINGNUMCDATSTIMSDATN TIMNUTCLONGCLNT LANGUNITCUKYRAW INT1 xxxxxxxxxxzz----------- INT2 xxxxxxxxxxzz----------- INT4 xxxxxxxxxxzz----------- INT8 xxxxxxxxxxzz----------- DEC xxxxxxxxxxzz----------- CURR xxxxxxxxxxzz----------- QUAN xxxxxxxxxxzz----------- DECFLOAT16 xxxxxxxxxxzz----------- DECFLOAT34 xxxxxxxxxxzz----------- DF16_DEC xxxx---xxx------------- DF34_DEC xxxx---xxx------------- FLTP xxxxxxxxxxzz----------- CHAR xxxxxxxxxxxxyyy---yycy- SSTRING xxxxxxxxxxxxyyy---yycy- NUMC xxxxxxxxxxyyyyy---y---- DATS xxxxxxxxxxxxyx-x------- TIMS xxxxxxxxxxxxy-x-x------ DATN -------------x-x------- TIMN --------------x-x------ UTCLONG -----------------x----- CLNT ----------xxy-----x---- LANG ----------xx-------x--- UNIT ----------xx--------x-- CUKY ----------xx---------x- RAW ----------------------c There are no further restrictions for combinations using x . The following prerequisites apply to the other combinations:
For combinations with y, the initial length cannot be less than the target length.
For combinations with z, the target length must be sufficient to represent the value in the source.
For combinations with c, the initial length and target length must be equal. These prerequisites are checked by the ABAP SQL parser. In the case of incompatible types, the content of the operand is converted to the target type. Exceptions can be raised if values are not suitable. If the operand of the expression has the null value, the result of the expression is also the null value.
Latest notes:
Specifying a cast expression always means specifying an SQL expression. Cast expressions can only be specified for operand positions in which SQL expressions are possible.
Type modifications can be used in operand positions of AB-SQL statements to convert operands without a suitable type to an operand with a suitable type.
CAST expressions are platform-independent with one exception: For conversions from the type FLTP to other numeric types the result is platform-dependent.
For conversions from the type FLTP to other types, rounding errors might occur. For conversions to character types depending on the value either the mathematical or scientific notation is generated and the case of the exponent character is not fixed. Converting back such a character representation to a floating data type always produces the original value.
For the missing combinations of type modifications that cannot be covered by a CAST expression, construction operators such as CONV can be used in host expressions, at least for literals and host variables. There are also built-in conversion functions for special conversions:
BINTOHEX and HEXTOBIN for conversions of byte strings to character strings and vice versa.
A cast expression cannot be evaluated in the table buffer and always causes table buffering to be bypassed. NON_V5_HINTS
If SQL expressions other than operands are used in a cast expression or if a data type other than FLTP is specified as dtype, the syntax check is performed in ABAP_STRICT_761 strict mode from ABAP_RELEASE ABAP_761 / . This mode handles the statement more strictly than the regular syntax check.
If INT8 is specified as dtype in a cast expression, the syntax check is performed in a ABAP_STRICT_762 strict mode from ABAP_RELEASE ABAP_762 / , which handles the statement more strictly than the regular syntax check. If used, D16N or D34N apply ABAP_STRICT_777 strict mode of the syntax check from ABAP_RELEASE ABAP_777 / . ABAP_HINT_END
ABAP_EXAMPLE_VX5 The following SELECT list splits a time stamp in a packed number into its date part and its time part. This requires multiple CAST expressions to create a suitable type in every operand position. ABEXA 01267 ABAP_EXAMPLE_END
