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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'a1843703b321f39e9877a6bb753683f02673725343d7532aa9ee16117eeefc23' 
  AND token = 'pxXh7S0YtNEixoQ6tQtXeN7XyGE5/vDxKhIE7ZA3JzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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