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ekappr_c
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Procedure
Abstract
Required_Reading
Keywords
Brief_I/O
Detailed_Input
Detailed_Output
Parameters
Exceptions
Files
Particulars
Examples
Restrictions
Literature_References
Author_and_Institution
Version
Index_Entries

Procedure

   void ekappr_c ( SpiceInt     handle,
                   SpiceInt     segno,
                   SpiceInt   * recno  ) 

Abstract

 
   Append a new, empty record at the end of a specified E-kernel 
   segment. 
 

Required_Reading

 
   EK 
 

Keywords

 
   PRIVATE 
   UTILITY 
 

Brief_I/O

 
   Variable  I/O  Description 
   --------  ---  -------------------------------------------------- 
   handle     I   File handle. 
   segno      I   Segment number. 
   recno      O   Number of appended record. 
 

Detailed_Input

 
   handle         is a file handle of an EK open for write access. 
 
   segno          is the number of the segment to which the record 
                  is to be added.  EK segment numbers range from
                  zero to N-1, where N is the number of segments
                  in the kernel.
 

Detailed_Output

 
   recno          is the number of the record appended by this 
                  routine.  recno is used to identify the record 
                  when writing column entries to it.  EK record
                  numbers range from 0 to N-1, where N is the
                  number of records in the segment containing
                  the record.
 

Parameters

 
   None. 
 

Exceptions

 
   1)  If handle is invalid, the error will be diagnosed by routines 
       called by this routine.  The file will not be modified. 
 
   2)  If segno is out of range, the error SPICE(INVALIDINDEX) 
       will be signalled.  The file will not be modified. 
 
   3)  If an I/O error occurs while reading or writing the indicated 
       file, the error will be diagnosed by routines called by this 
       routine.  The file may be corrupted. 
 

Files

 
   See the EK Required Reading for a discussion of the EK file 
   format. 
 

Particulars

 
   This routine operates by side effects:  It appends a new, empty 
   record structure to an EK segment.  The ordinal position of the 
   new record is one greater than the previous number of records in 
   in the segment. 
 
   After a new record has been appended to a segment by this routine, 
   the record must be populated with data using the ekace*_c 
   routines.  EKs are valid only when all of their column entries 
   are initialized. 
 
   To insert a record into a segment at a specified ordinal position, 
   use the routine ekappr_c. 
 
   This routine cannot be used with the "fast write" suite of 
   routines.  See the EK Required Reading for a discussion of the 
   fast writers. 
 

Examples

 
   1)  Append a record to a specified segment. 
 
       Suppose we have an E-kernel named order_db.ek which contains 
       records of orders for data products.  The E-kernel has a 
       table called DATAORDERS that consists of the set of columns 
       listed below: 
 
          DATAORDERS 
 
             Column Name     Data Type 
             -----------     --------- 
             ORDER_ID        INTEGER 
             CUSTOMER_ID     INTEGER 
             LAST_NAME       CHARACTER*(*) 
             FIRST_NAME      CHARACTER*(*) 
             ORDER_DATE      TIME 
             COST            DOUBLE PRECISION 
 
       The order database also has a table of items that have been 
       ordered.  The columns of this table are shown below: 
 
          DATAITEMS 
 
             Column Name     Data Type 
             -----------     --------- 
             ITEM_ID         INTEGER 
             ORDER_ID        INTEGER 
             ITEM_NAME       CHARACTER*(*) 
             DESCRIPTION     CHARACTER*(*) 
             PRICE           DOUBLE PRECISION 
 
 
       We'll suppose that the file order_db.ek contains two segments, 
       the first containing the DATAORDERS table and the second 
       containing the DATAITEMS table. 
 
       If we wanted to insert a new record into the DATAORDERS 
       table in position 0, we'd make the following calls: 


          #include "SpiceUsr.h"
              .
              . 
              . 
          /. 
          Open the database for write access.  This call is 
          made when the file already exists.  See ekopn_c for 
          an example of creating a new file. 
          ./
          ekopw_c ( "order_db.ek", &handle ); 
 
          /.   
          Append a new, empty record to the DATAORDERS 
          table. Recall that the DATAORDERS table 
          is in segment number 0.  The call will return 
          the number of the new, empty record. 
          ./ 
          ekappr_c ( handle, 0, &recno );
 
          /.
          At this point, the new record is empty.  A valid EK 
          cannot contain empty records.  We fill in the data 
          here.  Data items are filled in one column at a time. 
          The order in which the columns are filled in is not 
          important.  We use the ekace*_c (add column entry) 
          routines to fill in column entries.  We'll assume 
          that no entries are null.  All entries are scalar, 
          so the entry size is 1. 
          ./ 
          isnull  =  SPICEFALSE;
          size    =  1; 
 
          /.
          The following variables will contain the data for 
          the new record. 
          ./
          ordid    =   10011; 
          custid   =   531;
          lname    =   "scientist"; 
          fname    =   "joe";
          odate    =   "1995-sep-20"; 
          cost     =   5000.;
 
          /.
          Note that the names of the routines called 
          correspond to the data types of the columns:  the 
          last letter of the routine name is C, I, or D, 
          depending on the data type.  Time values are 
          converted to ET for storage. 
          ./ 
          ekacei_c ( handle,  segno,  recno, "order_id", 
                     size,    ordid,  isnull             ); 
 
          ekacei_c ( handle,  segno,  recno, "customer_id", 
                     size,    custid, isnull              ); 
 
          ekacec_c ( handle,  segno,  recno, "last_name", 
                     size,    vallen, lname,  isnull      );
 
          ekacec_c ( handle,  segno,  recno, "first_name", 
                     size,    vallen, fname,  isnull      ); 
  
          utc2et_c ( odate,   &et );
 

          ekaced_c ( handle, segno,  recno, "order_date", 
                     size,   et,     isnull               ); 
 
          ekaced_c ( handle, segno,  recno, "cost", 
                     size,   cost,   isnull               ); 
 
          /.
          Close the file to make the update permanent. 
          ./
          ekcls_c ( handle );
 
 

Restrictions

 
   None. 
 

Literature_References

 
   None. 
 

Author_and_Institution

 
   N.J. Bachman   (JPL) 
 

Version

 
   -CSPICE Version 1.0.0, 09-JAN-2002 (NJB)

Index_Entries

 
   append record to EK segment 
 
Wed Apr  5 17:54:33 2017