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  1                       Version 4.0 -- 5/1/89                  dbadlen
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  NAME:  dbadlen

  FUNCTION:
       Return the actual length of the data for a compute column.

  SYNTAX:
       DBINT dbadlen(dbproc, computeid, column)

       DBPROCESS *dbproc;
       int       computeid;
       int       column;








  dbadlen                 Version 4.0 -- 5/1/89                        2
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  COMMENTS:

       o This routine returns the actual length of the data for  a  par-
         ticular compute column.
       o Use the dbaltlen() routine to determine  the  maximum  possible
         length  for  the  data.   Use dbadata() to get a pointer to the
         data.

       o Here's  a  program  fragment  that  illustrates  the   use   of
         dbadlen():

         DBPROCESS       *dbproc;
         char            biggest_name[MAXNAME+1];
         int             namelen;
         int             rowinfo;

         /* put the command into the command buffer */


  3                       Version 4.0 -- 5/1/89                  dbadlen
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         dbcmd(dbproc, "select name from sysobjects");
         dbcmd(dbproc, " order by name");
         dbcmd(dbproc, " compute max(name)");

         /* send the command to SQL Server and start execution */
         dbsqlexec(dbproc);

         /* process the command */
         dbresults(dbproc);

         /* examine each row returned by the command */
         while ((rowinfo = dbnextrow(dbproc)) != NO_MORE_ROWS)
         {
             if (rowinfo == REG_ROW)
                 printf("regular row returned.\n");
             else
             {



  dbadlen                 Version 4.0 -- 5/1/89                        4
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                 /* This row is the result of a COMPUTE clause,
                  * and "rowinfo" is the computeid of this COMPUTE
                  * clause.
                  */

                 namelen = dbadlen(dbproc, rowinfo, 1);
                 strncpy
                  (biggest_name,
                   (char *)dbadata(dbproc, rowinfo, 1),
                   namelen);

                 /* Data pointed to by dbadata() is not
                  * null-terminated.
                  */
                 biggest_name[namelen] = '\0';

                 printf("biggest name = %s\n", biggest_name);



  5                       Version 4.0 -- 5/1/89                  dbadlen
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             }
         }


  PARAMETERS:
       dbproc -  A pointer to the DBPROCESS structure that provides  the
           connection for a particular front-end/SQL Server process.  It
           contains all the information that DB-Library uses  to  manage
           communications and data between the front end and SQL Server.
       computeid -  The id that identifies the particular compute row of
           interest.   A  SQL SELECT statement may have multiple COMPUTE
           clauses, each of which returns a separate compute  row.   The
           computeid  corresponding  to  the  first  COMPUTE clause in a
           SELECT is 1.  The computeid is  returned  by  dbnextrow()  or
           dbgetrow().
       column -  The number of the column of interest.  The first column
           is number 1.



  dbadlen                 Version 4.0 -- 5/1/89                        6
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  RETURNS:
       The length, in bytes,  of  the  data  for  a  particular  compute
       column.  If  there is no such column or COMPUTE clause, dbadlen()
       returns -1.  If the data has a null value, dbadlen() returns 0.

  SEE ALSO:
       dbadata, dbaltlen, dbalttype, dbgetrow, dbnextrow, dbnumalts