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SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '8888be0431bbc1a8d1aa0cc6d5b372ea573fc8efe4972dbe3a353ca4c29ae89f' 
  AND token = 'glyJltHz79SjtxTPrekVZe+0STBc7yNwmQRJxGLWIgs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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