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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbee0c8cee4f6fc86ba58e8cb1e8f1705d15c819bb4a977a1aacde433cfb7ff0' 
  AND token = 'wp33qlaS5AkcbAIHYwQxj9mQsRG9+O8e0tQglmRf3VA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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