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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b2e2b231de7eee2ce3c1a2739408fbf7e7436c90f28e3143a33625b56a70b82d' 
  AND token = '1NXD7tdLABPPbd4HU3QWKsAaycyTiipUVjT8diIrdT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}