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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '5b2c76e152966266d3bf43ec29c2c86a500f79975e75d56c828072625a667d74' 
  AND token = 'JXs6tCPeIar722ImTivZBYjNT7CchW7CXgnprM1MIdU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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