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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b5b1d36ca437fe92ecac5d9e1f35120138e5d9c79e173c68df0d2439e2ee4eb' 
  AND token = '4g5NeOjd4ZZ1Icv8EbjjzE3IYvVesFYxYydwI+8VdjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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