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To do this in the SQL editor, click the mouse where you want to start the selection and then press the Alt key (by default) while you extend the selection by dragging the mouse. If you prefer to use  the Ctrl key as the modifier, you can change the default in Tool Properties in the SQL Commander category under the General tab.

Tab Key Treatment

Pressing the TAB key in the editor inserts four space characters by default. If you instead want a TAB character to be inserted, or want to insert another number of space characters, you can specify this in the Tool Properties dialog, in the SQL Commander category under the General tab.

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