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professional-php-08-new-class.Database.php / php



  <?php
  
  require_once('config.php');
  require_once('DB.php');
  
  class Database {
    private conn;
  
    function __construct(dsn = null) {
      global conn;
      
      //If nothing was passed in, use the value from cfg
      if(dsn == null) {
        dsn = cfg['db']['dsn'];
      }
      
      //Open a connection using the info in dsn
      this->conn = DB::connect(dsn);
      
      if(DB::isError(this->conn)) {
        //We're not connected.  Throw an exception
        throw new Exception(this->conn->getMessage(), this->conn->getCode());
      }
      
      //Always fetch data as an associative array
      this->conn->setFetchMode(DB_FETCHMODE_ASSOC);
    }
    
    //returns a DB_result object  
    function select(sql) {
      result = this->conn->query(sql);
     
      if(DB::isError(result)) {
        throw new Exception(result->getMessage(), result->getCode());
      }
      
      return result;
    }
    
    //returns 2D assoc array
    function getAll(sql) {
      result = this->conn->getAll(sql);
     
      if(DB::isError(result)) {
        throw new Exception(result->getMessage(), result->getCode());
      }
      
      return result;
    }
    
    //returns single scalar value from the first column, first record
    function getOne(sql) {
      result = this->conn->getOne(sql);
      
      if(DB::isError(result)) {
        throw new Exception(result->getMessage(), result->getCode());
      }
      
      return result;
    }
    
    //returns numerically indexed 1D array of values from the first column
    function getColumn(sql) {
      result = this->conn->getCol(sql);
      
      if(DB::isError(result)) {
        throw new Exception(result->getMessage(), result->getCode());
      }
      
      return result;
    }
    function update(tableName, arUpdates, sWhere = null) {
      
      arSet = array();
      foreach(arUpdates as name => value) {
        arSet[] = name . ' = ' . this->conn->quoteSmart(value);
      }
      sSet = implode(', ', arSet);
  
      //make sure the table name is properly escaped
      tableName = this->conn->quoteIdentifier(tableName);   
  
      sql = "UPDATE tableName SET sSet";
      if(sWhere) {
        sql .= " WHERE sWhere";
      }
      
      result = this->conn->query(sql);
      
      if(DB::isError(result)) {
        throw new Exception(result->getMessage(), result->getCode());
      }
      
      //return the number of rows affected
      return this->conn->affectedRows();
    }
  function insert(tableName, arValues) {
      id = null;
        
      sFieldList = join(', ', array_keys(arValues));
      
      arValueList = array();
      foreach(arValues as value) {
        if(strtolower(value) == '#id#') {
          //we need to get the next value from this table's sequence
          value = id = this->conn->nextID(tableName . "_id");
        }   
        arValueList[] = this->conn->quoteSmart(value);
      }
      sValueList = implode(', ', arValueList);
      
      //make sure the table name is properly escaped
      tableName = this->conn->quoteIdentifier(tableName);
      
      sql = "INSERT INTO tableName ( sFieldList) VALUES ( sValueList )";
      result = this->conn->query(sql);
      
      if(DB::isError(result)) {
        throw new Exception(result->getMessage(), result->getCode());
      }
      
      //return the ID, if there was one, or the number of rows affected
      return id ? id : this->conn->affectedRows();
    }
    function startTransaction() {
      //autoCommit returns true/false if the command succeeds
      return this->conn->autoCommit(false);
    }
    function commit() {
      result = this->conn->commit();
      
      if(DB::isError(result)) {
        throw new Exception(result->getMessage(), result->getCode());
      }
      
      this->conn->autoCommit(true);
      return true;
    }
    
    function abort() {
      result = this->conn->rollback();
      
      if(DB::isError(result)) {
        throw new Exception(result->getMessage(), result->getCode());
      }
      
      return true;
    }
    
    
    function __destruct() {
      this->conn->disconnect();
    }
  }
  ?>
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

(C) Æliens 20/2/2008

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