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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cb0e8085aaceb0963d73ac4a088ddf520ffaf4cd41eb2ead234b330a2e1b7d1b' 
  AND token = 'NaNRvPvOl0Qo9KZtmWFBiBcSSwxiSd+Ks9ph1EBEXkI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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