How to execute SELECT * LIKE statement with a placeholder in sqlite?

Question

I've got an argument tag and I perfomed this way:

cursor.execute("SELECT * FROM posts WHERE tags LIKE '%?%'", (tag,))

but it doesn't seem to work.
I'm new to sqlite, please tell me how to fix it. Thx !

Answer 1

Apply the wildcards to the parameter, not the SQL:

cursor.execute("SELECT * FROM posts WHERE tags LIKE ?", (f'%{tag}%',))

The ? SQL parameter interpolation adds quoting for you, so your query ends up as '%'value'%', which is not valid SQL.