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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb8aaf549ca3dccf16d7bf006563082d00c2275726c5dfe6ff4338646dc16cdd' 
  AND token = 'KzAL6B3Rc0FDp+zgtCoKyMYSJiqKxUKFguAFpWJN4bU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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