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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f9ab0dcd59826c1d2fe383f8b6a3dd129fd4a1c1f1ed1c9b332c923c059a6a1c' 
  AND token = 'zmJqOvZy82br1WbQqUtJrrg1XP4YhLFshl01+d+Nd3U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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