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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69d6031912732aa63cf1a7bea21ec6a390fd5f3c6ed62bb941f8e546619a43ca' 
  AND token = 'ZlJ6acNpuJ3cYnw2ZibPMiY3IUW8b4LVHJJOgr0g44w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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