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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'befec7b88290c0bcf86d014ec99921afad1bfc1d1e340c14154f5cd6c17ce50b' 
  AND token = 'dk3Sa9eL7zP31aX1N3vcKTFpDK/7Dx8+lABA+UkcOcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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