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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e53c6876991bd0d60aeb2aba94f329e050159c8519092ba9ad895f36c54cf4da' 
  AND token = 'csjQYYfiMKgbRj1PS1G3ObsovR7stLj//BTQLyNcvpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}