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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '710c37f9a83ae44460846f43ec6683f8bd667223e02b137a4ab5cf15e6f42b18' 
  AND token = 'I9tNZNvPWIkWmf4Yi+Wys3VDrI7HzofScHqj/qM7DUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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