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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64b3875612f5a2f65d096e8bad1004261815b32136e6c10d452fd21166995444' 
  AND token = '6xhDfPrShuZHoN1Esd/exRiokeefSkB//LMdAzx8+ko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}