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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e647e5ecdbdbfff1b9f6768e49e36b5ae19a4ad5f557e4f3ff25324c4f251466' 
  AND token = 'JEg1h7nZ8NY1lgmYJ8/Uj+JqfnbWI6cAF2LEioLturI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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