When selecting and viewing data using a client application such as Interactive SQL, unexpected symbols such as squares, arrows, and question marks, may appear as characters in the data.

There are two main reasons why this can happen. The first reason is because there is a problem with the underlying data that is stored in the database. For example, if character set conversion was required when the data was inserted into the database, and some characters in the original character set did not have an equivalent character in the database character set, then substitution characters were inserted instead.

The second, and more common, reason why unexpected symbols can appear in the client application is because the font used to display the data does not support the characters. You can resolve this problem by changing to a Unicode font. If it is not possible to change the font for the client application, you can also change the operating system default font.

For example, suppose you are on a Windows system that uses the standard English font (Tahoma), which does not support the display of Japanese characters. However, your database character set is cp932 and the database contains Japanese data, and when you query the database, characters in the results display as small boxes. In Interactive SQL, you can change the font used to display results by choosing Tools » Options » Results » Font, and specifying a Unicode font such as Arial Unicode MS, or Lucida Sans Unicode. Unicode fonts are a good choice because they are capable of displaying characters from many languages.

If your client application does not provide font settings that you can change, it is likely using your default operating system font. In this case, consult your operating system documentation for information about how to change the default system font, and change it to a Unicode font.

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