I wang import data from a txt file to the sqlite,the txt file separator by x'01', who can tell me how to set separator in the sqlite? Thank you very much!

If you are using the CLI's .import command, I believe your column separator MUST be a non-null character (x'01' is the null character).

Consider replacing the null separator by another character: can you use the conventional comma as the column separator?

x'01' is the null character

No, it is not. x'00' would be NUL, and x'01' would be SOH.

From the CLI, this worked for me:

SQLite version 3.39.2 2022-07-21 15:24:47
Enter ".help" for usage hints.
sqlite> .separator "\01"
sqlite> .import e:/temp/ajay.txt t10
sqlite> select * from t10;
name      factor
--------  ------
ajay      100.78
askoolum  200.78
sqlite>

Don't forget to substitute your file name and table name, as appropriate.

In my text editor, e:/temp/ajay.txt looks like:

name
factor
ajay
100.78
askoolum
200.78

Example:

knu@f7p3:~ $ echo abc^Adef>tmp/tmp.in
knu@f7p3:~ $ echo ghi^Ajkl>>tmp/tmp.in
knu@f7p3:~ $ rm -f tmp/test.sqlite ; sqlite3 tmp/test.sqlite ".separator ^A" ".import 'tmp/tmp.in' newtab" ".tables" ".mode column"  "SELECT * FROM newtab"
newtab
abc  def
---  ---
ghi  jkl

Note: x01 is the same as Ctrl+A .

In a Linux or Unix system, you can enter that on the command line or in vi by typing Ctrl+V followed by Ctrl+A

-- 
Regards,
Kees NUyt