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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '666e50c0eed806d2b42854a35a40829d1139b3a365a2c50d6ff80cd9bf303fe6' 
  AND token = 'NsiFtcbH4QGURtJ1OvZbiQpNJGiZOYEbMPQqWZB9mdo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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