SELECT field
    , field1
    , field2
...

   SELECT  polls.`uid`, polls.`valid_days`
     FROM  yr_polls as polls
LEFT JOIN  yr_polls_choice as choice
       ON  polls.uid = choice.poll_id
    WHERE  polls.uid = p_id

Или

    UPDATE yr_polls_choice as pc
       SET pc.`choice` = 'aaaa'
     WHERE pc.`uid` = 1;

SELECT
    field1, , ..., fieldN
    fieldN+1, ... fieldN+M
FROM table AS t1
LEFT JOIN table2 AS t2 ON t2.field = t1.field
LEFT JOIN table3 AS t3 ON t3.field = t1.field AND t3.field2 = t2.fieldX
WHERE t3.field = 'something' AND t1.field = 'nothing' AND
        t2.field = 'anything'
ORDER BY t1.id DESC
GROUP BY t2.field
LIMIT 0, 10

             $query = $db->select()
                         ->from('apartaments')
                         ->join(
                                 'apartaments_types',
                                 'apartaments.atype = apartaments_types.atype',
                                 array(
                                     'atype_name'
                                 )
                             )
                         ->join(
                                 'apartaments_pricetype', 
                                 'apartaments.pricetype = apartaments_pricetype.id', 
                                 array(
                                     'pricetype_text' => 'apartaments_pricetype.description'
                                 )
                            )
                         ->where('uid = ?', $id)
                         ->where('df = ?', 0)
                         ;

#Gets Nike's products
SELECT
	DISTINCT types.*
FROM
	(
		SELECT
			products.id,
			products.name,
			products.item,
			products.brand,
			products.sex,
			products.season
		FROM
			products
		INNER JOIN
			display
			ON
			display.item = products.season
			AND
			MID(
				IF(
					LENGTH(display.status) < 3,
					CONCAT(
						REPEAT(
							0,
							3 - LENGTH(display.status)
						),
						display.status
					),
					display.status
				),
				1,
				1
			) = 1
		INNER JOIN
			types
			ON
			types.brand = products.brand
			AND
			types.sex = products.sex
			AND
			types.season = products.season
		WHERE
			display.page = 289
		LIMIT	100
	) AS activeProducts
INNER JOIN
	types
	ON
	types.id = activeProducts.sex
WHERE
	types.brand = 'nike'

SELECT t1.a, t1.b, t3,t, t3.s
       t2.c, t2.d, t3.h
  FROM db.table1 AS t1 
 INNER JOIN db.table2 AS t2 ON t1.g=t2.j
 INNER JOIN db.table3 AS t2 ON t3.g=t2.l
 WHERE t1.u > 10 
   AND t2.u > 10
   AND t3 < 10
 GROUP BY t2.a ASC
 ORDER BY t1.a DESC
 LIMIT 10

SELECT
	`t`.`field`
,	`t`.`field1` `another_field`

FROM
	`table` `t`
	INNER JOIN `table1` `t1` ON (`t1`.`id` = `t`.`id`)
	LEFT JOIN `table2` `t2` ON (`t2`.`id` = `t1`.`id`)
WHERE
	`t`.`value` = 'foo'
	AND `t1`.`value` = 'bar'
GROUP BY
	`t`.`field`
ORDER BY
	`t`.`field` DESC