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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd6cbbb9fcba610dfaae7e5cb1e0927a4516337f2b951ca81133f548c25ab71d7' 
  AND token = 'MPpA4BZx+kHQ4TWRudlikdwQ8kd+8wa3jI1fBNP8SWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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