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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1823baea61ac34394fd33331ca4ca1b73c87d1c37b18bbe0bea22c0d442edec' 
  AND token = 'Mt2CqYA6RBgJ6V2/1NDX4nVXOXq2xYHeYtoExQQ1/Ig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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