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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f2a2cf7dc00db3ceb31e111c06c6cf5e4dcab5ec041b58bd26cbab76d75b123a' 
  AND token = 'LMxmmKApYQHqiDggzi4VBEoDqvqvYXtToQZYRs0ODaY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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