[CakePHP 2.3.9]'column <>' => $valueで期待する動作をしない事があったので次の3パターンを試す

検証

$valueがscalarの場合(問題ない)

• 問題なく動作する。

$value = 1;
$this->Comment->find('all', array(
    'conditions' => array(
        'id <>' => $value,
    ),
));

• 次のようなSQLができた。

SELECT "Comment"."id" AS "Comment__id"
FROM "public"."comments" AS "Comment"
WHERE "id" <> 1

$valueがarrayで2件以上含まれる場合(問題ない)

• 問題なく動作する。

$value = array(2, 3);
$this->Comment->find('all', array(
    'conditions' => array(
        'id <>' => $value,
    ),
));

• 次のようなSQLができた。

SELECT "Comment"."id" AS "Comment__id"
FROM "public"."comments" AS "Comment"
WHERE "id" NOT IN (2, 3)

$valueがarrayで1件のみ含まれる場合(問題あり)

• 問題が生じて動作しない。

$value = array(4);
$this->Comment->find('all', array(
    'conditions' => array(
        'id <>' => $value,
    ),
));

• 次のようなSQLができた。

SELECT "Comment"."id" AS "Comment__id"
FROM "public"."comments" AS "Comment"
WHERE id <> = (4)

Error: SQLSTATE[42883]: Undefined function: 7 ERROR: operator does not exist: integer <> LINE 1: ...d" FROM "public"."comments" AS "Comment" WHERE id <> = (4) ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.

'NOT' => array('column' => $value)だと安全な様子

$valueがscalarの場合

$value = 1;
$this->Comment->find('all', array(
    'conditions' => array(
        'NOT' => array(
            'id' => $value,
        ),
    ),
));

SELECT "Comment"."id" AS "Comment__id"
FROM "public"."comments" AS "Comment"
WHERE NOT ("id" = 1)

$valueがarrayで2件以上含まれる場合

$value = array(2, 3);
$this->Comment->find('all', array(
    'conditions' => array(
        'NOT' => array(
            'id' => $value,
        ),
    ),
));

SELECT "Comment"."id" AS "Comment__id"
FROM "public"."comments" AS "Comment"
WHERE NOT ("id" IN (2, 3))

$valueがarrayで1件のみ含まれる場合

$value = array(4);
$this->Comment->find('all', array(
    'conditions' => array(
        'NOT' => array(
            'id' => $value,
        ),
    ),
));

SELECT "Comment"."id" AS "Comment__id"
FROM "public"."comments" AS "Comment"
WHERE NOT (id = (4))