lib/dml/database_column_info.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Database column information.
  19  *
  20  * @package    core_dml
  21  * @copyright  2008 Petr Skoda (http://skodak.org)
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 defined('MOODLE_INTERNAL') || die();
  26
  27 /**
  28  * Detailed database field information.
  29  *
  30  * It is based on the adodb library's ADOFieldObject object.
  31  * 'column' does mean 'the field' here.
  32  *
  33  * @package    core_dml
  34  * @copyright  2008 Petr Skoda (http://skodak.org)
  35  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  36  */
  37 class database_column_info {
  38     /**
  39      * Name of column - lowercase.
  40      * @var string
  41      */
  42     public $name;
  43
  44     /**
  45      * Driver dependent native data type.
  46      * Not standardised, its used to find meta_type.
  47      * @var string
  48      */
  49     public $type;
  50
  51     /**
  52      * Max length:
  53      *  character type - number of characters
  54      *  blob - number of bytes
  55      *  integer - number of digits
  56      *  float - digits left from floating point
  57      *  boolean - 1
  58      * @var int
  59      */
  60     public $max_length;
  61
  62     /**
  63      * Scale
  64      * float - decimal points
  65      * other - null
  66      * @var int
  67      */
  68     public $scale;
  69
  70     /**
  71      * True if not null, false otherwise
  72      * @var bool
  73      */
  74     public $not_null;
  75
  76     /**
  77      * True if column is primary key.
  78      * (usually 'id').
  79      * @var bool
  80      */
  81     public $primary_key;
  82
  83     /**
  84      * True if filed autoincrementing
  85      * (usually 'id' only)
  86      * @var bool
  87      */
  88     public $auto_increment;
  89
  90     /**
  91      * True if binary
  92      * @var bool
  93      */
  94     public $binary;
  95
  96     /**
  97      * True if integer unsigned, false if signed.
  98      * Null for other types
  99      * @var integer
 100      * @deprecated since 2.3
 101      */
 102     public $unsigned;
 103
 104     /**
 105      * True if the default value is defined.
 106      * @var bool
 107      */
 108     public $has_default;
 109
 110     /**
 111      * The default value (if defined).
 112      * @var string
 113      */
 114     public $default_value;
 115
 116     /**
 117      * True if field values are unique, false if not.
 118      * @var bool
 119      */
 120     public $unique;
 121
 122     /**
 123      * Standardised one character column type, uppercased and enumerated as follows:
 124      * R - counter (integer primary key)
 125      * I - integers
 126      * N - numbers (floats)
 127      * C - characters and strings
 128      * X - texts
 129      * B - binary blobs
 130      * L - boolean (1 bit)
 131      * T - timestamp - unsupported
 132      * D - date - unsupported
 133      * @var string
 134      */
 135     public $meta_type;
 136
 137     /**
 138      * Constructor
 139      * @param mixed $data object or array with properties
 140      */
 141     public function __construct($data) {
 142         foreach ($data as $key=>$value) {
 143             if (property_exists($this, $key)) {
 144                 $this->$key = $value;
 145             }
 146         }
 147
 148         switch ($this->meta_type) {
 149             case 'R': // normalise counters (usually 'id')
 150                 $this->binary         = false;
 151                 $this->has_default    = false;
 152                 $this->default_value  = null;
 153                 $this->unique         = true;
 154                 break;
 155             case 'C':
 156                 $this->auto_increment = false;
 157                 $this->binary         = false;
 158                 break;
 159         }
 160     }
 161 }