Update README.md

README.md

@@ -36,21 +36,11 @@ Some fields in Post/Tags use my custom enum field to store type/category or some
   * 4: meta
 
 #### Tag List
-SQLite doesn't support any arrayfield or many-to-many relationship natively.<br>
-So I use a custom TextField to store ids of tags belongs to a Post.
+I use peewee ManyToManyField to implement the Tag List things. Which utilize a through model which have all the pair of Tag and Post<br>
+Since it is very likely we will want to use Tag to query posts, so many-to-many is better.<br>
+The con of this design is the database file will be 1.5x larger than before(we have 0.25B entries for the post-tag pairs), but the query speed become 2~3x faster, so I think it is acceptable.
 
-The basic idea is to use 2 unique symbol for start/end of the number. And use 36-base number<br>
-(python support converting n-base number into integer natively, numpy have utils to convert integer into n-base number)
-
-I use $xxx# format, so when you want to utilize the FTS table to search tag_list, use $\<36-base number\># to find if the tag is in the tag-list.
-
-For example:<br>
-The code in profiling.py use $6KMR# which is 306675 under base-36.<br>
-So the profiling.py is doing "fetch all the Post object which have 'umamusume' tag in their tag list"<br>
-**If you can ensure the tag type, you can specific the tag_list_\<type\> instead of full tag_list for more efficiency**
-
-## Profiling
-A test script for showing why I use FTS.
+After done some checking, I can ensure that all the "categorical tag list" can be done by full list + filter, and that is how I done it now. Check the db.py for more details.
 
 
 #### Utils