git.m6w6.name Git - m6w6/pq-gateway/blob - lib/pq/Gateway/Table/Identity.php

   1 <?php
   2
   3 namespace pq\Gateway\Table;
   4
   5 use \pq\Gateway\Table;
   6
   7 const IDENTITY_SQL = <<<SQL
   8 select
   9  a.attname as column
  10 from  pg_class     c
  11  join pg_index     i  on c.oid    = i.indrelid
  12  join pg_attribute a  on c.oid    = a.attrelid
  13 where
  14      c.relname = \$1
  15  and a.attnum  = any(i.indkey)
  16  and i.indisprimary
  17 order by
  18  a.attnum
  19 SQL;
  20
  21 /**
  22  * A primary key implementation
  23  */
  24 class Identity implements \Countable, \IteratorAggregate
  25 {
  26         /**
  27          * @var array
  28          */
  29         protected $columns = array();
  30
  31         /**
  32          * @param \pq\Gateway\Table $table
  33          */
  34         function __construct(Table $table) {
  35                 $cache = $table->getMetadataCache();
  36                 if (!($this->columns = $cache->get("$table#identity"))) {
  37                         $table->getQueryExecutor()->execute(
  38                                 new \pq\Query\Writer(IDENTITY_SQL, array($table->getName())),
  39                                 function($result) use($table, $cache) {
  40                                         $this->columns = array_map("current", $result->fetchAll(\pq\Result::FETCH_ARRAY));
  41                                         $cache->set("$table#identity", $this->columns);
  42                                 }
  43                         );
  44                 }
  45         }
  46
  47         /**
  48          * @implements \Countable
  49          * @return int
  50          */
  51         function count() {
  52                 return count($this->columns);
  53         }
  54
  55         /**
  56          * @implements \IteratorAggregate
  57          * @return \ArrayIterator
  58          */
  59         function getIterator() {
  60                 return new \ArrayIterator($this->columns);
  61         }
  62
  63         /**
  64          * Get the column names which the primary key contains
  65          * @return array
  66          */
  67         function getColumns() {
  68                 return $this->columns;
  69         }
  70 }