phplib_sybase.php

来自「最近在做软交换时研究的一个软交换的东东」· PHP 代码 · 共 240 行

<?php
/*
 * Session Management for PHP3
 *
 * Copyright (c) 1998-2000 NetUSE AG
 *                    Boris Erdmann, Kristian Koehntopp
 *
 * Adapted from db_mysql.inc by Sascha Schumann <[e-mail]>
 *
 * modified by Ben Drushell http://www.technobreeze.com/
 *
 * metadata() contributed by Adelino Monteiro <[e-mail]>
 *
 * $Id: phplib_sybase.php 173 2005-03-13 20:34:07Z rcourtna $
 *
 */

class DB_Sql {
  var $Host     = "";
  var $Database = "";
  var $User     = "";
  var $Password = "";

  var $Link_ID  = 0;
  var $Query_ID = 0;
  var $Record   = array();
  var $Row;

  var $Auto_Free = 0;     ## Set this to 1 for automatic sybase_free_result()
  var $Halt_On_Error = "report"; ## "yes" (halt with message), "no" (ignore errors quietly), "report" (ignore errror, but spit a warning)
  var $Seq_Table     = "db_sequence";

  /* public: constructor */
  function DB_Sql($query = "") {
      $this->query($query);
  }

  function connect() {
    if ( 0 == $this->Link_ID ) {
      $this->Link_ID=sybase_pconnect($this->Host,$this->User,$this->Password);
      if (!$this->Link_ID) {
        $this->halt("Link-ID == false, pconnect failed");
      }
      if(!sybase_select_db($this->Database, $this->Link_ID)) {
        $this->halt("cannot use database ".$this->Database);
      }
    }
    return($this->Link_ID);
  }

  function query($Query_String) {


    /* No empty queries, please, since PHP4 chokes on them. */
    if ($Query_String == "")
      /* The empty query string is passed on from the constructor,
       * when calling the class without a query, e.g. in situations
       * like these: '$db = new DB_Sql_Subclass;'
       */
      return 0;

    $this->connect();

#   printf("Debug: query = %s<br>\n", $Query_String);

    $this->Query_ID = sybase_query($Query_String,$this->Link_ID);
    $this->Row   = 0;
    if (!$this->Query_ID) {
      $this->halt("Invalid SQL: ".$Query_String);
    }

    return $this->Query_ID;
  }

  function next_record() {
    $this->Record = sybase_fetch_array($this->Query_ID);
    $this->Row   += 1;

    $stat = is_array($this->Record);
    if (!$stat && $this->Auto_Free) {
      sybase_free_result($this->Query_ID);
      $this->Query_ID = 0;
    }
    return $stat;
  }

  function seek($pos) {
    $status = sybase_data_seek($this->Query_ID, $pos);
    if ($status)
      $this->Row = $pos;
    return;
  }

  function metadata($table) {
      $count = 0;
      $id    = 0;
      $res   = array();

      $this->connect();
      $result = $this->query("exec sp_columns $table");
      if ($result < 0) {
          $this->Errno = 1;
          $this->Error = "Metadata query failed";
          $this->halt("Metadata query failed.");
      }
      $count = sybase_num_rows($result);

      for ($i=0; $i<$count; $i++) {
          $res[$i]["table"] = $table ;
          $res[$i]["name"]  = sybase_result ($result, $i, "COLUMN_NAME");
          $res[$i]["type"]  = sybase_result ($result, $i, "TYPE_NAME");
          $res[$i]["len"]   = sybase_result ($result, $i, "LENGTH");
          $res[$i]["position"] = sybase_result ($result, $i, "ORDINAL_POSITION");
          $res[$i]["flags"] = sybase_result ($result, $i, "REMARKS");

      }
  }

  function affected_rows() {
    return sybase_affected_rows($this->Query_ID);
  }

  function num_rows() {
    return sybase_num_rows($this->Query_ID);
  }

  function num_fields() {
    return sybase_num_fields($this->Query_ID);
  }

  function nf() {
    return $this->num_rows();
  }

  function np() {
    print $this->num_rows();
  }

  function f($Name) {
    return $this->Record[$Name];
  }

  function p($Name) {
    print $this->Record[$Name];
  }

  function halt($msg) {
    if ($this->Halt_On_Error == "no")
      return;

    printf("</td></tr></table><b>Database error:</b> %s<br>\n", $msg);
    printf("<b>Sybase Error</b><br>\n");

    if ($this->Halt_On_Error != "report")
      die("Session halted.");
  }

/* public: table locking */
  function lock($table, $mode="write") {
    $this->connect();

    $query="LOCK TABLE $table IN SHARE MODE;";
    $res = @sybase_query($query,$this->Link_ID);
    if (!$res) {
      $this->halt("lock($table, $mode) failed.");
      return 0;
    }
    return $res;
  }

/* public: table unlocking */
  function unlock() {
    $this->connect();

    $query="COMMIT;";
    $res = @sybase_query($query,$this->Link_ID);
    if (!$res) {
      $this->halt("unlock() failed.");
      return 0;
    }
    return $res;
  }

  /* public: sequence numbers */
  function nextid($seq_name) {
    $this->connect();

    if ($this->lock($this->Seq_Table)) {
      /* get sequence number (locked) and increment */
      $q  = sprintf("select nextid from %s where seq_name = '%s'",
                $this->Seq_Table,
                $seq_name);
      $id  = @sybase_query($q, $this->Link_ID);
      $res = @sybase_fetch_array($id);

      /* No current value, make one */
      if (!is_array($res)) {
        $currentid = 0;
        $q = sprintf("insert into %s values('%s', %s)",
                 $this->Seq_Table,
                 $seq_name,
                 $currentid);
        $id = @sybase_query($q, $this->Link_ID);
      } else {
        $currentid = $res["nextid"];
      }
      $nextid = $currentid + 1;
      $q = sprintf("update %s set nextid = '%s' where seq_name = '%s'",
               $this->Seq_Table,
               $nextid,
               $seq_name);
      $id = @sybase_query($q, $this->Link_ID);
      $this->unlock();
    } else {
      $this->halt("cannot lock ".$this->Seq_Table." - has it been created?");
      return 0;
    }
    return $nextid;
  }

  /* public: sequence numbers */
  function currentid($seq_name) {
    $this->connect();

    $currentid = 0;
    $q  = sprintf("select nextid from %s where seq_name = '%s'",
              $this->Seq_Table,
              $seq_name);
    $id  = @sybase_query($q, $this->Link_ID);
    $res = @sybase_fetch_array($id);

    /* No current value, make one */
    if (is_array($res)) {
      $currentid = $res["nextid"];
    }
    return $currentid;
  }
}
?>