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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd3e7f2d75e5b096839a8246235f515e111c665d50a6a439eb93d85b3261da69b' 
  AND token = '28x/iqWFCSMrS32Pa/vLgdtezDESl/zLYIm0eyZdwbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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