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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f694140ba6eced7bbdb2a124880d39e19e9cced34dea23bf303ca9fc6ac6c376' 
  AND token = 'GSrzqkop7XN/Arw1Rkc064g+cyYi4Z6i+HS9oMNjNsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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