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To set a breakpoint, put the cursor on a statement, use the Toggle Breakpoint command in the ribbon or right-click and choose Set As Breakpoint from the context menu. You can also press the F9 key. Only lines with executable commands may have breakpoints. For example, you cannot set a breakpoint on a comment line or GROUP_BY command.
You can open other objects for editing during the debug session and set breakpoints where required.
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