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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8b9bce7d53ba9a7f294f7fc00e8dc6e2af720861a55b17f5dcd9a5401482635f' 
  AND token = 'f7+ubzjjfKnZ3Mc/WuSJayOSLNnAXmNHjH3iPUip0PM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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