SQLDA Structure Usage
You use the SQLDA (SQL Descriptor Area) to pass type and size information about an SQL statement, an Ingres form, or an Ingres table field, between Ingres and your program.
To use the SQLDA, issue the include sqlda statement in each subprogram of your source file that references the SQLDA. The include sqlda statement generates a Fortran include directive to a file that defines the SQLDA structure type. The file does not declare an SQLDA variable; your program must declare a variable of the specified type. You can also code this structure variable directly instead of using the include sqlda statement. You can choose any name for the structure.
The definition of the SQLDA (as specified in the include file) is:
UNIX:
C
C Single element of SQLDA variable
C
structure /IISQLVAR/
integer*2 sqltype
integer*2 sqllen
integer*4 sqldata
integer*4 sqlind
structure /IISQLNAME/ sqlname
integer*2 sqlname1
character*34 sqlnamec
end structure
end structure
C
C Maximum number of columns returned from Ingres
C
parameter (IISQ_MAX_COLS = 1024)
C
C IISQLDA - SQLDA with maximum number of entries
C for variables.
C
structure /IISQLDA/
character*8 sqldaid
integer*4 sqldabc
integer*2 sqln
integer*2 sqld
record /IISQLVAR/ sqlvar(IISQ_MAX_COLS)
end structure
structure /IISQLHDLR/
C Optional argument to pass through
integer*4 sqlarg
C user-defined datahandler function
integer*4 sqlhdlr
end structure
C
C Allocation sizes
C
parameter (IISQDA_HEAD_SIZE = 16,
1 IISQDA_VAR_SIZE = 48)
C
C Type and length codes
C
C
parameter (IISQ_DTE_TYPE = 3,
1 IISQ_MNY_TYPE = 5,
2 IISQ_DEC_TYPE = 10,
3 IISQ_CHA_TYPE = 20,
4 IISQ_VCH_TYPE = 21,
5 IISQ_LVCH_TYPE = 22,
6 IISQ_INT_TYPE = 30,
7 IISQ_FLT_TYPE = 31,
8 IISQ_OBJ_TYPE = 45,
9 IISQ_HDLR_TYPE = 46,
1 IISQ_TBL_TYPE = 52,
2 IISQ_DTE_LEN = 25)
parameter (IISQ_LVCH_TYPE = 22,
1 IISQ_HDLR_TYPE = 46)
VMS:
structure /IISQLVAR/ ! Single SQLDA variable
integer*2 sqltype
integer*2 sqllen
integer*4 sqldata ! Address of any type
integer*4 sqlind ! Address of 2-byte integer
structure /IISQLNAME/ sqlname
integer*2 sqlname1
character*34 sqlnamec
end structure
end structure
parameter IISQ_MAX_COLS = 1024 ! Maximum number of
C columns
structure /IISQLDA/
character*8 sqldaid
integer*4 sqldabc
integer*2 sqln
integer*2 sqld
record /IISQLVAR/ sqlvar(IISQ_MAX_COLS)
end structure
structure /IISQLHDR/
integer*4 sqlarg ! Optional argument to pass
integer*4 sqlhdlr ! User-defined datahandler fn
end structure
! Type codes
parameter IISQ_DTE_TYPE = 3, ! Date - Output
1 IISQ_MNY_TYPE = 5, ! Money - Output
2 IISQ_DEC_TYPE = 10, ! Decimal - Output
3 IISQ_CHA_TYPE = 20, ! Char - Input, Output
4 IISQ_VCH_TYPE = 21, ! Varchar - Input, Output
5 IISQ_LVCH_TYPE= 22, ! Long Varchar - Input,Output
6 IISQ_INT_TYPE = 30, ! Integer - Input, Output
7 IISQ_FLT_TYPE = 31, ! Float - Input, Output
8 IISQ_OBJ_TYPE = 45, ! 4GL Object: Output
9 IISQ_HDLR_TYPE= 46, ! IISQLHDLR: Datahandler
1 IISQ_TBL_TYPE = 52, ! Table Field - Output
2 IISQ_DTE_LEN = 25, ! Date length
! Allocation sizes
parameter IISQDA_VAR_SIZE = 16,
1 IISQDA_VAR = 48
parameter IISQ_LVCH_TYPE = 22,
1 IISQ_HDLR_TYPE = 46
Windows:
structure /IISQLVAR/
integer*2 sqltype
integer*2 sqllen
integer*4 sqldata ! Address of any type
integer*4 sqlind ! Address of 2-byte integer
structure /IISQLNAME/ sqlname
integer*2 sqlnamel
character*34 sqlnamec
end structure
end structure
C
C IISQ_MAX_COLS - Maximum number of columns returned from INGRES
C
parameter IISQ_MAX_COLS = 1024
C
C IISQLDA - SQLDA with maximum number of entries for variables.
C
structure /IISQLDA/
character*8 sqldaid
integer*4 sqldabc
integer*2 sqln
integer*2 sqld
record /IISQLVAR/ sqlvar(IISQ_MAX_COLS)
end structure
C
C IISQLHDLR - Structure type with function pointer and function argument
C for the DATAHANDLER.
C
structure /IISQLHDLR/
integer*4 sqlarg
integer*4 sqlhdlr
end structure
C
C Allocation sizes - When allocating an SQLDA for the size use:
C IISQDA_HEAD_SIZE + (N * IISQDA_VAR_SIZE)
C
parameter IISQDA_HEAD_SIZE = 16,
1 IISQDA_VAR_SIZE = 48
C
C Type and Length Codes
C
parameter IISQ_DTE_TYPE = 3, ! Date - Output
1 IISQ_MNY_TYPE = 5, ! Money - Output
2 IISQ_DEC_TYPE = 10, ! Decimal - Output
3 IISQ_CHA_TYPE = 20, ! Char - Input, Output
4 IISQ_VCH_TYPE = 21, ! Varchar - Input, Output
5 IISQ_INT_TYPE = 30, ! Integer - Input, Output
6 IISQ_FLT_TYPE = 31, ! Float - Input, Output
7 IISQ_TBL_TYPE = 52, ! Table field - Output
8 IISQ_DTE_LEN = 25 ! Date length
parameter IISQ_LVCH_TYPE = 22 ! Long varchar
parameter IISQ_LBIT_TYPE = 16 ! Long bit
parameter IISQ_HDLR_TYPE = 46 ! Datahandler
parameter IISQ_BYTE_TYPE = 23 ! Byte - Input, Output
parameter IISQ_VBYTE_TYPE = 24 ! Byte Varying - Input, Output
parameter IISQ_LBYTE_TYPE = 25 ! Long Byte - Output
parameter IISQ_OBJ_TYPE = 45 ! Object - Output
Structure Definition and Usage Notes:
• The structure type definition of the SQLDA is called IISQLDA. This is done so that an SQLDA variable may be called "SQLDA" without causing a compile-time conflict.
• The sqlvar array is an array of IISQ_MAX_COLS (1024) elements. If a variable of type IISQLDA is declared, the program will have a variable of IISQ_MAX_COLS elements.
• The sqlvar array begins at subscript 1.
• If your program defines its own SQLDA type, you must confirm that the structure layout is identical to that of the IISQLDA structure type, although you can declare a different number of sqlvar elements.
• The nested structure
sqlname is a varying length character string consisting of a length and data area. The
sqlnamec field contains the name of a result field or column after the
describe (or
prepare into) statement. The length of the name is specified by
sqlnamel. The characters in the
sqlnamec field are blank padded. The
sqlname structure can also be set by a program using Dynamic FRS. The program is not required to pad
sqlname with blanks. see
How to Set SQLNAME for Dynamic FRS in this chapter.
• The list of type codes represents the types that are returned by the describe statement, and the types used by the program when using an SQLDA to retrieve or set data. The type code IISQ_TBL_TYPE indicates a table field and is set by the FRS when describing a form that contains a table field.
