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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5dceb31161eaf40c3f54ebcc358f148b9ece3081d286b9546bb0f5dd9321634' 
  AND token = 'SFSxmc8LwUXMlXHHJlbYpyDuI3I9OC/lX1b+DpnUJqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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