Fossil

      " WHERE mtime<=julianday('%qz') AND type GLOB '%q'"
      " ORDER BY mtime DESC LIMIT 1",
      &zTag[4], zType);
    return rid;
  }

  /* "tag:" + symbolic-name */
  if( memcmp(zTag, "tag:", 4)==0
   || memcmp(zTag, "root:", 5)==0
  ){
    int isRoot = zTag[0]=='r';
    rid = db_int(0,
       "SELECT event.objid"
       "  FROM tag, tagxref, event"
       " WHERE tag.tagname='sym-%q' "
       "   AND tagxref.tagid=tag.tagid AND tagxref.tagtype>0 "
       "   AND event.objid=tagxref.rid "
       "   AND event.type GLOB '%q'"
       " ORDER BY event.mtime DESC /*sort*/",
       &zTag[4+isRoot], zType
    );

    if( isRoot && rid>0 ){


      Stmt q;
      int rc;

      db_prepare(&q,
        "SELECT pid, EXISTS(SELECT 1 FROM tagxref"
                           " WHERE tagid=%d AND tagtype>0"
                           "   AND value=%Q AND rid=plink.pid)"
        "  FROM plink"
        " WHERE cid=:cid AND isprim",
        TAG_BRANCH, &zTag[5]
      );
      do{
        db_reset(&q);
        db_bind_int(&q, ":cid", rid);
        rc = db_step(&q);
        if( rc!=SQLITE_ROW ) break;
        rid = db_column_int(&q, 0);
      }while( db_column_int(&q, 1)==1 && rid>0 );
      db_finalize(&q);
    }
    return rid;
  }

  /* symbolic-name ":" date-time */
  nTag = strlen(zTag);
  for(i=0; i<nTag-10 && zTag[i]!=':'; i++){}
  if( zTag[i]==':' && is_date(&zTag[i+1]) ){