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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b2d69b2f10a84a964b6eb0a79a554a8a7084d3181b53d9968dd049666d2c966d' 
  AND token = 'SCOll16VTRM9ffj+1gZXkCNLoWi6vF0MLHx3hwEVSaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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