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SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    655, 656, 657, 658, 659, 660, 661, 662, 
    663, 664, 665, 666, 667, 668, 669, 670, 
    671, 672, 673, 674, 675, 676, 677, 678, 
    679, 680, 681, 682, 683, 684, 685, 686, 
    687, 688, 689, 690
  ) 
  AND category_id != 264

Query time 0.00028

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	cscart_categories	ALL	PRIMARY,parent,p_category_id				214	Using where