What is wrong with this SQLite3 statement?

I have written this SQLite statement and I am getting syntax error on the following line:

update List SET number = (CASE WHEN number>=3 then number++ WHEN number=1 the开发者_如何转开发n 3 ELSE number END) WHERE listKey=3;

The error is:

SQL error: near "WHEN": syntax error

I tried various versions, adding braces at places and all, but can't figure out the error. Can anyone please help me with this?

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If SQLite uses "++" syntax, I've never seen it. Try then number + 1 instead.