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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'cb521e4f3fb3e253322213e5b08b33bfb5268d10cef41ba0c1822b5136ee2910' 
  AND token = 'kR0ACEp1k43so00rM/2P9HfgH8BUJ2QPKWb6dhTQ0uw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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