phplib_mssql.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 295 行

<?php
/*
 * Session Management for PHP3
 *
 * (C) Copyright 1998 Cameron Taggart ([e-mail])
 *      Modified by Guarneri carmelo ([e-mail])
 *      Modified by Cameron Just     ([e-mail])
 *      Modified by Ben Drushell     (http://www.technobreeze.com/)
 *
 * $Id: phplib_mssql.php 173 2005-03-13 20:34:07Z rcourtna $
 */
# echo "<BR>This is using the MSSQL class<BR>";

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

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

  var $Errno    = 0;
  var $Error    = "";

  var $Auto_Free = 0;     ## set this to 1 to automatically free results

  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";

  /* copied from db_mysql for completeness */
  /* public: identification constant. never change this. */
  var $type     = "mssql";
  var $revision = "1.2";

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

  function connect() {
    if ( 0 == $this->Link_ID ) {
      $this->Link_ID=mssql_pconnect($this->Host, $this->User, $this->Password);
      if (!$this->Link_ID)
        $this->halt("Link-ID == false, mssql_pconnect failed");
      else
          mssql_select_db($this->Database, $this->Link_ID);
    }
  }
  function free_result(){
      mssql_free_result($this->Query_ID);
      $this->Query_ID = 0;
  }
  
  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;

      if (!$this->Link_ID)
        $this->connect();
    
#   printf("<br>Debug: query = %s<br>\n", $Query_String);
    
    $this->Query_ID = mssql_query($Query_String, $this->Link_ID);
    $this->Row = 0;
    if (!$this->Query_ID) {
      $this->Errno = 1;
      $this->Error = "General Error (The MSSQL interface cannot return detailed error messages).";
      $this->halt("Invalid SQL: ".$Query_String);
    }
    return $this->Query_ID;
  }
  
  function next_record() {
      
    if ($this->Record = mssql_fetch_row($this->Query_ID)) {
      // add to Record[<key>]
      $count = mssql_num_fields($this->Query_ID);
      for ($i=0; $i<$count; $i++){
          $fieldinfo = mssql_fetch_field($this->Query_ID,$i);
        $this->Record[strtolower($fieldinfo->name)] = $this->Record[$i];
      }
      $this->Row += 1;
      $stat = 1;
    } else {
      if ($this->Auto_Free) {
            $this->free_result();
          }
      $stat = 0;
    }
    return $stat;
  }
  
  function seek($pos) {
        mssql_data_seek($this->Query_ID,$pos);
      $this->Row = $pos;
  }

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

    $this->connect();
    $id = mssql_query("select * from $table", $this->Link_ID);
    if (!$id) {
      $this->Errno = 1;
      $this->Error = "General Error (The MSSQL interface cannot return detailed error messages).";
      $this->halt("Metadata query failed.");
    }
    $count = mssql_num_fields($id);
    
    for ($i=0; $i<$count; $i++) {
        $info = mssql_fetch_field($id, $i);
      $res[$i]["table"] = $table;
      $res[$i]["name"]  = $info["name"];
      $res[$i]["len"]   = $info["max_length"];
      $res[$i]["flags"] = $info["numeric"];
    }
    $this->free_result();
    return $res;
  }
  
  function affected_rows() {
    return mssql_affected_rows($this->Query_ID);
  }
  
  function num_rows() {
    return mssql_num_rows($this->Query_ID);
  }
  
  function num_fields() {
    return mssql_num_fields($this->Query_ID);
  }

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

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

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

  function p($Field_Name) {
    print $this->f($Field_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>MSSQL Error</b>: %s (%s)<br>\n",
      $this->Errno,
      $this->Error);
    if($this->Halt_On_Error != "report")
      die("Session halted.");
  }

/* public: table locking
 * Table locking is automatic in MS SQL and Access.
 * However, the automatic locking is based on session
 *  and transaction.
 * To better assure locking occurs at a certain area of
 *  a script the transaction statement is used.
 */
  function lock($table, $mode="write") {
    if($this->Transaction_Status) {
      $this->halt("transaction in progress... look for abandoned transaction");
      return 0;
    }

    $this->connect();

    $query="BEGIN TRANSACTION";
    $res = @mssql_query($query,$this->Link_ID);
    if (!$res) {
      $this->halt("transaction begin failed.");
      $this->Transaction_Status = 0;
      return 0;
    }
    $this->Transaction_Status = 1;
    return $res;
  }

/* public: table unlocking
 * Table locking is automatic in MS SQL and Access.
 * However, the automatic locking is based on database
 *  sessions and transactions.
 * To better assure locking occurs at a certain area of
 *  a script the transaction statement is used.
 */
  function unlock() {
    $this->connect();

    if($this->Transaction_Status) {
      $query="COMMIT TRANSACTION";
      $res = @mssql_query($query,$this->Link_ID);
      $this->Transaction_Status = 0;
      if (!$res) {
        $this->halt("transaction commit failed.");
        return 0;
      }
    } else {
      $query="COMMIT";
      $res = @mssql_query($query,$this->Link_ID);
    }
    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);
      $id  = @mssql_query($q, $this->Link_ID);

      if ($res = mssql_fetch_row($id)) {
        // add to res[<key>]
        $count = mssql_num_fields($id);
        for ($i=0; $i<$count; $i++){
          $fieldinfo = mssql_fetch_field($id,$i);
          $res[strtolower($fieldinfo->name)] = $res[$i];
        }
      }

      /* 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);
        $id = @mssql_query($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);
      $id = @mssql_query($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);
    $id  = @mssql_query($q, $this->Link_ID);

    if ($res = mssql_fetch_row($id)) {
      // add to res[<key>]
      $count = mssql_num_fields($id);
      for ($i=0; $i<$count; $i++){
        $fieldinfo = mssql_fetch_field($id,$i);
        $res[strtolower($fieldinfo->name)] = $res[$i];
      }
    }

    if (is_array($res)) {
      $currentid = $res["nextid"];
    }
    return $currentid;
  }
}
?>