db_mysql.inc
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上传日期:2007-01-04
资源大小:58k
文件大小:10k
- <?php
- /*
- * Session Management for PHP3
- *
- * Copyright (c) 1998,1999 SH Online Dienst GmbH
- * Boris Erdmann, Kristian Koehntopp
- *
- * $Id: db_mysql.inc,v 1.2 2000/04/11 14:46:24 prenagha Exp $
- *
- */
- class DB_Sql {
-
- /* public: connection parameters */
- var $Host = "";
- var $Database = "";
- var $User = "";
- var $Password = "";
- /* public: configuration parameters */
- var $Auto_Free = 0; ## Set to 1 for automatic mysql_free_result()
- var $Debug = 0; ## Set to 1 for debugging messages.
- var $Halt_On_Error = "yes"; ## "yes" (halt with message), "no" (ignore errors quietly), "report" (ignore errror, but spit a warning)
- var $Seq_Table = "db_sequence";
- /* public: result array and current row number */
- var $Record = array();
- var $Row;
- /* public: current error number and error text */
- var $Errno = 0;
- var $Error = "";
- /* public: this is an api revision, not a CVS revision. */
- var $type = "mysql";
- var $revision = "1.2";
- /* private: link and query handles */
- var $Link_ID = 0;
- var $Query_ID = 0;
-
- /* public: constructor */
- function DB_Sql($query = "") {
- $this->query($query);
- }
- /* public: some trivial reporting */
- function link_id() {
- return $this->Link_ID;
- }
- function query_id() {
- return $this->Query_ID;
- }
- /* public: connection management */
- function connect($Database = "", $Host = "", $User = "", $Password = "") {
- /* Handle defaults */
- if ("" == $Database)
- $Database = $this->Database;
- if ("" == $Host)
- $Host = $this->Host;
- if ("" == $User)
- $User = $this->User;
- if ("" == $Password)
- $Password = $this->Password;
-
- /* establish connection, select database */
- if ( 0 == $this->Link_ID ) {
-
- $this->Link_ID=mysql_pconnect($Host, $User, $Password);
- if (!$this->Link_ID) {
- $this->halt("pconnect($Host, $User, $Password) failed.");
- return 0;
- }
- if (!@mysql_select_db($Database,$this->Link_ID)) {
- $this->halt("cannot use database ".$this->Database);
- return 0;
- }
- }
-
- return $this->Link_ID;
- }
- /* public: discard the query result */
- function free() {
- @mysql_free_result($this->Query_ID);
- $this->Query_ID = 0;
- }
- /* public: perform a query */
- function query($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 (!$this->connect()) {
- return 0; /* we already complained in connect() about that. */
- };
- # New query, discard previous result.
- if ($this->Query_ID) {
- $this->free();
- }
- if ($this->Debug)
- printf("Debug: query = %s<br>n", $Query_String);
- $this->Query_ID = @mysql_query($Query_String,$this->Link_ID);
- $this->Row = 0;
- $this->Errno = mysql_errno();
- $this->Error = mysql_error();
- if (!$this->Query_ID) {
- $this->halt("Invalid SQL: ".$Query_String);
- }
- # Will return nada if it fails. That's fine.
- return $this->Query_ID;
- }
- /* public: walk result set */
- function next_record() {
- if (!$this->Query_ID) {
- $this->halt("next_record called with no query pending.");
- return 0;
- }
- $this->Record = @mysql_fetch_array($this->Query_ID);
- $this->Row += 1;
- $this->Errno = mysql_errno();
- $this->Error = mysql_error();
- $stat = is_array($this->Record);
- if (!$stat && $this->Auto_Free) {
- $this->free();
- }
- return $stat;
- }
- /* public: position in result set */
- function seek($pos = 0) {
- $status = @mysql_data_seek($this->Query_ID, $pos);
- if ($status)
- $this->Row = $pos;
- else {
- $this->halt("seek($pos) failed: result has ".$this->num_rows()." rows");
- /* half assed attempt to save the day,
- * but do not consider this documented or even
- * desireable behaviour.
- */
- @mysql_data_seek($this->Query_ID, $this->num_rows());
- $this->Row = $this->num_rows;
- return 0;
- }
- return 1;
- }
- /* public: table locking */
- function lock($table, $mode="write") {
- $this->connect();
-
- $query="lock tables ";
- if (is_array($table)) {
- while (list($key,$value)=each($table)) {
- if ($key=="read" && $key!=0) {
- $query.="$value read, ";
- } else {
- $query.="$value $mode, ";
- }
- }
- $query=substr($query,0,-2);
- } else {
- $query.="$table $mode";
- }
- $res = @mysql_query($query, $this->Link_ID);
- if (!$res) {
- $this->halt("lock($table, $mode) failed.");
- return 0;
- }
- return $res;
- }
-
- function unlock() {
- $this->connect();
- $res = @mysql_query("unlock tables");
- if (!$res) {
- $this->halt("unlock() failed.");
- return 0;
- }
- return $res;
- }
- /* public: evaluate the result (size, width) */
- function affected_rows() {
- return @mysql_affected_rows($this->Link_ID);
- }
- function num_rows() {
- return @mysql_num_rows($this->Query_ID);
- }
- function num_fields() {
- return @mysql_num_fields($this->Query_ID);
- }
- /* public: shorthand notation */
- 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];
- }
- /* 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);
- $id = @mysql_query($q, $this->Link_ID);
- $res = @mysql_fetch_array($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);
- $id = @mysql_query($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);
- $id = @mysql_query($q, $this->Link_ID);
- $this->unlock();
- } else {
- $this->halt("cannot lock ".$this->Seq_Table." - has it been created?");
- return 0;
- }
- return $nextid;
- }
- /* public: return table metadata */
- function metadata($table='',$full=false) {
- $count = 0;
- $id = 0;
- $res = array();
- /*
- * Due to compatibility problems with Table we changed the behavior
- * of metadata();
- * depending on $full, metadata returns the following values:
- *
- * - full is false (default):
- * $result[]:
- * [0]["table"] table name
- * [0]["name"] field name
- * [0]["type"] field type
- * [0]["len"] field length
- * [0]["flags"] field flags
- *
- * - full is true
- * $result[]:
- * ["num_fields"] number of metadata records
- * [0]["table"] table name
- * [0]["name"] field name
- * [0]["type"] field type
- * [0]["len"] field length
- * [0]["flags"] field flags
- * ["meta"][field name] index of field named "field name"
- * The last one is used, if you have a field name, but no index.
- * Test: if (isset($result['meta']['myfield'])) { ...
- */
- // if no $table specified, assume that we are working with a query
- // result
- if ($table) {
- $this->connect();
- $id = @mysql_list_fields($this->Database, $table);
- if (!$id)
- $this->halt("Metadata query failed.");
- } else {
- $id = $this->Query_ID;
- if (!$id)
- $this->halt("No query specified.");
- }
-
- $count = @mysql_num_fields($id);
- // made this IF due to performance (one if is faster than $count if's)
- if (!$full) {
- for ($i=0; $i<$count; $i++) {
- $res[$i]["table"] = @mysql_field_table ($id, $i);
- $res[$i]["name"] = @mysql_field_name ($id, $i);
- $res[$i]["type"] = @mysql_field_type ($id, $i);
- $res[$i]["len"] = @mysql_field_len ($id, $i);
- $res[$i]["flags"] = @mysql_field_flags ($id, $i);
- }
- } else { // full
- $res["num_fields"]= $count;
-
- for ($i=0; $i<$count; $i++) {
- $res[$i]["table"] = @mysql_field_table ($id, $i);
- $res[$i]["name"] = @mysql_field_name ($id, $i);
- $res[$i]["type"] = @mysql_field_type ($id, $i);
- $res[$i]["len"] = @mysql_field_len ($id, $i);
- $res[$i]["flags"] = @mysql_field_flags ($id, $i);
- $res["meta"][$res[$i]["name"]] = $i;
- }
- }
-
- // free the result only if we were called on a table
- if ($table) @mysql_free_result($id);
- return $res;
- }
- /* private: error handling */
- function halt($msg) {
- $this->Error = @mysql_error($this->Link_ID);
- $this->Errno = @mysql_errno($this->Link_ID);
- if ($this->Halt_On_Error == "no")
- return;
- $this->haltmsg($msg);
- if ($this->Halt_On_Error != "report")
- die("Session halted.");
- }
- function haltmsg($msg) {
- printf("</td></tr></table><b>Database error:</b> %s<br>n", $msg);
- printf("<b>MySQL Error</b>: %s (%s)<br>n",
- $this->Errno,
- $this->Error);
- }
- function table_names() {
- $this->query("SHOW TABLES");
- $i=0;
- while ($info=mysql_fetch_row($this->Query_ID))
- {
- $return[$i]["table_name"]= $info[0];
- $return[$i]["tablespace_name"]=$this->Database;
- $return[$i]["database"]=$this->Database;
- $i++;
- }
- return $return;
- }
- }
- ?>