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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8df4a2d0920551d3536e39a0ae1554fe72838116fc9b76643d13c5257beaf7e' 
  AND token = '0tdLnKWctIkIDkQswTx5WPk3Qxfha952sD6Olw6/OCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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