How to backup WhatsApp chats (not media) to save my phone memory? This answer explains how to save your chat on google drive and recently I got that option on WhatsApp. It says the backup will be stored on Drive as well as on my sd card, ok fine.

When I started my Google drive backup even it showed Backing up 110MB but I don't want to backup the whatsapp media (I just want to backup the text messages). Even if I backup entire 110MB to Drive and delete all my media and text messages (to clear up the space consumed by whatsapp), what will happen on next backup? Will it overwrite the last backup and substitute a new backup consisting of nothing?  

I got to know that there is some third party apps like Helium which can do this work. But is there something I can do without consuming more of my phone memory?
WhatsApp automatically makes backups every day at 3 AM and stores them in the WhatsApp folder of your Android phone. This folder is either located in your device's internal memory or external SD card. You can set the automatic backup in WhatsApp or manually use the "Back up chats" option in Whatsapp Settings,

  Whatsapp &gt; Settings &gt; Chats and calls &gt; Backup up chats 


This will store a backup file(usually named msgstore.db.crypt8) in your Main storage &gt; Whatsapp &gt; Databases directory which includes only the text messages in an encrypted format.

For individual export of chat messages without including media, as mentioned in the Whatsapp FAQ:


  To export a copy of the history of an individual chat or group, use
  the Email chat feature:
  
  
  Tap and hold on the conversation or group.
  Select Email chat.
  Choose whether to Attach Media or not.
  
  
  An email will be composed with your chat history attached as a .txt
  document.
  
  Note:
  
  
  If you choose to attach media, the most recent media sent will be added as attachments.
  When sending with media, you can send up to 10,000 latest messages. Without media, you can send 40,000 messages. These constraints are due
  to maximum email sizes.
  




You can now keep this backup in your mail or download it to your phone for later use. If you want to restore the messages, read this article, How do I restore my messages? for more information.