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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df4f3e39f35e490656af5df2e8e76b5f0c53140f9701c6eb87911a5fa8650074' 
  AND token = 'Kkh5WggySka/Uz6Ezno9ut0SQVGOm6gsLrMXLeiaCHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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