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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23ef81fb1849c86da0f5aaca01077019328306cbcee30f9ba50c2dd154e31d2e' 
  AND token = 'tQYQXG5qlIDzkxFmAZ8TQ9s0L+OjK8LhNoWMX+SQ5fg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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