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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '5d89ba578b1f2fbd3e81d29a0d60d90ac5e3342ac85588f77296863cbc17341c' 
  AND token = 'jiiZCQ6w5fWSu5SUJVotTom0cdWriYpKjLugRFy8m7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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