SQL in RPG - overlaying an external DS

Have found what would seem to be a SQL compiler error. Could be a
"feature" not sure.

I am trying to create a shorter version of field ctdtype as ctdtype4.
ctdtype is a field in file ctd.

this shell version of the program compiles just fine. The field ctdtype4
is defined using the clear statement.

D sq S
1024
D
D* DS FOR SQL INPUT
FIELDS
D DATA E DS
EXTNAME(CTD)
D CTDTYPE4
OVERLAY(CTDTYPE)
C clear CTDTYPE4
4
/FREE
EXEC SQL CLOSE
C1;
EXEC SQL PREPARE P1 FROM
:sq;
EXEC SQL DECLARE C1 SCROLL CURSOR FOR
P1;
EXEC SQL OPEN C1
;
EXEC SQL FETCH C1 INTO :DATA
;
/END-FREE
C seton lr


if instead I program it like this and define the field length of ctdtype4
on the d spec instead of the c spec
the compile listing has an additional field in the sql "fetch" data
structure
during debug you can watch it read in field sql_00044 (blanks) into field
ctdtype4 and wipe out the value in field ctdtype
no warnings on the compile listing.

D sq S
1024
D
D* DS FOR SQL INPUT
FIELDS
D DATA E DS
EXTNAME(CTD)
D CTDTYPE4 4
OVERLAY(CTDTYPE)
/FREE
EXEC SQL CLOSE
C1;
EXEC SQL PREPARE P1 FROM
:sq;
EXEC SQL DECLARE C1 SCROLL CURSOR FOR
P1;
EXEC SQL OPEN C1
;
EXEC SQL FETCH C1 INTO :DATA
;
/END-FREE
C seton lr

just thought you sql freaks might like to see it.


notes from the compile listing
fetch data structure from 1st program

D DS
FETCH
D SQL_00012 1 2B 0 INZ(128)
length of header
D SQL_00013 3 4B 0 INZ(5)
statement number
D SQL_00014 5 8B 0 INZ(0)
invocation mark
D SQL_00015 9 9A INZ('0')
data is okay
D SQL_00016 10 127A
end of header
D SQL_00017 129 129A
CTDRC
D SQL_00018 130 139A
CTDTYPE
D SQL_00019 140 149A
CTDTYPESB
D SQL_00020 150 158S 0
CTDNKEY1
D SQL_00021 159 163S 0
CTDNKEY2
D SQL_00022 164 193A
CTDAKEY1
D SQL_00023 194 223A
CTDAKEY2
D SQL_00024 224 233A
CTDMTHD
D SQL_00025 234 283A
CTDDESC
D SQL_00026 284 343A
CTDADDR
D SQL_00027 344 346A
CTDEBY
D SQL_00028 347 352S 0
CTDEMDY
D SQL_00029 353 358S 0
CTDEHMS
D SQL_00030 359 368A
CTDEJOB
D SQL_00031 369 378A
CTDEUSER
D SQL_00032 379 384A
CTDENBR
D SQL_00033 385 387A
CTDCBY
D SQL_00034 388 393S 0
CTDCMDY
D SQL_00035 394 399S 0
CTDCHMS
D SQL_00036 400 409A
CTDCJOB
D SQL_00037 410 419A
CTDCUSER
D SQL_00038 420 425A
CTDCNBR
D SQL_00039 426 432S 0
CTDCUST
D SQL_00040 433 434S 0
CTDCSTB
D SQL_00041 435 441S 0
CTDVEND
D SQL_00042 442 444S 0
CTDSLMN
D SQL_00043 445 447A
CTDEMP

the second program adds this line at the end of the data structure
D SQL_00044 448 451A
CTDTYPE4


Jim Horn

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