You want to make a setup with database? check this
How to deploy C# windows application With Sql Server?[
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Or you want to give him an update to do changes in existing database? Couple of ways
0) Make a database script file & you could directly execute that
1) Create a batch file & execute the database script using
sqlcmd Utility[
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2) Make a simple UI form which connects the existing database, in button click call the execute database script file
Now you decide which one is secure/better for you.