lib/dml/database_column_info.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18
  19 /**
  20  * Database column information.
  21  *
  22  * @package    core
  23  * @subpackage dml
  24  * @copyright  2008 Petr Skoda (http://skodak.org)
  25  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  26  */
  27
  28 defined('MOODLE_INTERNAL') || die();
  29
  30 /**
  31  * Detail database field information.
  32  * Based on ADOFieldObject.
  33  */
  34 class database_column_info {
  35     /**
  36      * Name of column - lowercase
  37      */
  38     public $name;
  39
  40     /**
  41      * Driver dependent native data type
  42      * Not standardised - used to find meta_type
  43      */
  44     public $type;
  45
  46     /**
  47      * Max length:
  48      *  character type - number of characters
  49      *  blob - number of bytes
  50      *  integer - number of digits
  51      *  float - digits left from floating point
  52      *  boolean - 1
  53      *  enums - null
  54      */
  55     public $max_length;
  56
  57     /**
  58      * Scale
  59      * float - decimal points
  60      * other - null
  61      */
  62     public $scale;
  63
  64     /**
  65      * Enumerated field options,
  66      * null if not enum type
  67      *
  68      * For performance reasons this field is optional!
  69      * You can use DDL sql_generator::getCheckConstraintsFromDB() if needed.
  70      */
  71     public $enums;
  72
  73     /**
  74      * True if not null, false otherwise
  75      */
  76     public $not_null;
  77
  78     /**
  79      * True if column is primary key.
  80      * (usually 'id').
  81      */
  82     public $primary_key;
  83
  84     /**
  85      * True if filed autoincrementing
  86      * (usually 'id' only)
  87      */
  88     public $auto_increment;
  89
  90     /**
  91      * True if binary
  92      */
  93     public $binary;
  94
  95     /**
  96      * True if integer unsigned, false if signed.
  97      * Null for other types
  98      */
  99     public $unsigned;
 100
 101     /**
 102      * True if default value defined
 103      */
 104     public $has_default;
 105
 106     /**
 107      * Default value if defined
 108      */
 109     public $default_value;
 110
 111     /**
 112      * True if field values unique, false if not
 113      */
 114     public $unique;
 115
 116     /**
 117      * Standardised one character column type, uppercase
 118      * R - counter (integer primary key)
 119      * I - integers
 120      * N - numbers (floats)
 121      * C - characters and strings
 122      * X - texts
 123      * B - binary blobs
 124      * L - boolean (1 bit)
 125      * T - timestamp - unsupported
 126      * D - date - unsupported
 127      */
 128     public $meta_type;
 129
 130     /**
 131      * Constructor
 132      * @param $data mixed object or array with properties
 133      */
 134     public function __construct($data) {
 135         foreach ($data as $key=>$value) {
 136             if (property_exists($this, $key)) {
 137                 $this->$key = $value;
 138             }
 139         }
 140
 141         switch ($this->meta_type) {
 142             case 'R': // normalise counters (usually 'id')
 143                 $this->auto_increment = true;
 144                 $this->binary         = false;
 145                 $this->has_default    = false;
 146                 $this->default_value  = null;
 147                 $this->unique         = true;
 148                 break;
 149             case 'C':
 150                 $this->auto_increment = false;
 151                 $this->binary         = false;
 152                 break;
 153         }
 154     }
 155 }