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SELECT 
  tax_id, 
  address_type, 
  priority, 
  price_includes_tax, 
  regnumber 
FROM 
  cscart_taxes 
WHERE 
  tax_id IN (6) 
  AND status = 'A' 
ORDER BY 
  priority

Query time 0.00030

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	cscart_taxes	system	PRIMARY,c_status				1

Result

tax_id	address_type	priority	price_includes_tax	regnumber
6	S	1	N