GeoServer layer preview doesn't work for chinese columns or columns that has underscore in name

Question

I am learning to use GeoServer. I published a layer from a shp, which I created by importing a csv file into QGIS in utf-8 encoding, and exporting as shp in utf-8 encoding. I added a style to the layer. I got the style from geoserver cookbook for point with default label. The only thing I changed is the contents in <ogc:PropertyName>, as I have to set it to the name of the column I want to show. I changed it into school_name. But then the layer doesn't show in layer preview.

Things I've tried:

1. change <ogc:PropertyName> content to the column lat. This column contains latitude. The type shown on GeoServer is double. This works.
2. change <ogc:PropertyName> content to school. This column contains Chinese characters. The type shown on GeoServer is string. The layer shows but the labels are ??.
3. change <ogc:PropertyName> content to school and change the xml encoding to utf-8 and UTF-8. Again, the layer shows, but the labels are ??
4. change <ogc:PropertyName> content to school and add format_options=CHARSET:UTF-8 in the WMS request. Again, the layer shows, but the labels are ??.
5. change content to postal_code. This column contains postcodes which are just numbers. The type shown on GeoServer is long. The layer doesn't show.

So how do I show Chinese labels? And how do I fix the problem where column names with underscore doesn't show?

Answer 1

Here's how my problem was eventually fixed. I made two key mistakes regarding the Chinese character problem (dbf encoding encoding setting in data store and font in sld), and one mistake regarding the underscore problem (column name length).

Chinese Character Problem

This is actually an encoding and font problem. The first mistake I made was not setting the dbf encoding when creating the data store of shp directories. To fix these mistakes, set the dbf encoding as in the image. In this case the correct encoding is utf8 (see figure).

The second mistake I made is using font Arial (the font from the cookbook), this caused the characters to appear as boxes. To fix this mistake, change the font to DFKai-SB, which is a font for Chinese characters. I didn't test with other fonts for Chinese characters, but I assume they will work as well.

(EDITED) Underscore Problem

This is actually a problem with the length of the column name of shp files. school_name and postal_code both have 11 characters. It seems shp will truncate after 10 characters. Opening the attribute table of the shp in QGIS, I found that the column names were school_nam and postal_nam. So the problem was fixed by changing <ogc:PropertyName> content to school_nam. Also, checking the Feature Type Details on GeoServer tells me the column names I should use (see figure).

note: The layer created from the csv in QGIS had the correct column names. But after exporting it as a shp and re-importing it to QGIS, I could see that the names were truncated. So take caution that the column names of the shp may be different from the original layer used to create it.