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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e342797ca2adc73b76c0e286d9f7a6add43eec8d763e0ec1a4137b213fdd1f33' 
  AND token = 'wkz9qVFy+mZuLP+Mu7Be0z6WAIrGIIg/WmcpulgBpDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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