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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9baa2e13d1bbc04880c09ea8f868e9efdb326cd2f5e55dc91ee62ad09073a16c' 
  AND token = 'A8YGR9Vh4xh/BAPJfyfk+hqGYNNmbrP7b7Pj1br5vrE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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