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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4be75dcb96bc8f0b2ac1f9bcb066ba1d8e742ba9bc1f923a467bee2311b5bd25' 
  AND token = 'TSFagul0Am5O2PyI9QFixhYgEYDSqeIvdm2g7Ll71Y8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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