Version: Next

The minimum concepts you need

For designers: you do not need to understand code generation. Remember the points below so you can talk with engineering and avoid common mistakes.

Three things

Tables must be registered first: Engineering registers the table in __tables__ (or XML). Only then will your Excel be exported. Creating an xlsx on your machine alone does not put it into the build.
Headers have rules: Cells near the top-left that start with ## are the header area, not normal data. If A1 does not start with ##, the tool treats that sheet as missing.
Client and server may see different columns: In ##group, c / s say who gets the column. Wrong values cause “client missing field” or “sensitive numbers leak to the client”.

##var	id	name	price	drop_weight	#note
##type	int	string	int	int
##group		c,s	c	s
##	Item ID	Name	Price	Drop weight	Designer note
	1001	Gold	0	100	Base currency

What you see	What it means
`##var` row	English field names (for code)
`##type` row	Types (set by engineering—do not change casually)
`##group` row	`c` = client, `s` = server
`#note` column	Comment column—not shipped into the game
Data rows	Content that is actually exported

You	Engineering
Fill values under the header; tune numbers	Decide field types, primary keys, which columns go to the client
Fill nested / polymorphic fields from sample sheets	Define structures, subtype names and aliases
Request “add a column xxx”	Update the Schema, then tell you where and how to fill the new column
Paste the full error when generation fails	Fix types or refs from the row/column location

Do not change type names in ##type (for example, changing int to “integer”).
Do not unmerge header cells that engineering merged, and do not drag columns around randomly.
Do not assume “a file under Datas will export”—it must be registered first.