SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ed83750736b94f3453607c51d4c72be94bb49495745fe42572fb456ab03fd6b' 
  AND token = '+pY8C6NcgFTwcoCnQjKdH1Vi7vGvxo2XJ0D+hgqyYCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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