We Learn SQL #8 | NULLs

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  • Опубликовано: 9 ноя 2024
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Комментарии • 8

  • @lizli6217
    @lizli6217 Год назад +1

    It's very clear and I love SQL series for beginners! Thanks a lot!

  • @roshnakabdulsalam7944
    @roshnakabdulsalam7944 Год назад +1

    Concise and too easy to understand. Thanks, Adrian

  • @thorstenl.4928
    @thorstenl.4928 9 месяцев назад

    Good overview. Thanks.
    I'd like to add one thing to keep in mind.
    It seems easy to consider this and use is null instead.
    However the pitfall is, when you compare against a column value (e.g. in a join), where null values exist.
    Or when you use optional user inputs and try something like this:
    tbl.col = NVL({input}, tbl.col)
    When this columns contains nulls then this becomes tbl.col = null what fails.
    (Here the solution could be tbl.col = {input} or {input} is null)
    The danger is, when you get a good looking resultset and don't recognize, that you compare against null!

  • @Kkarthikvm
    @Kkarthikvm Год назад +1

    Nice explanation 😊

  • @veeek8
    @veeek8 Год назад

    Really clear videos, great stuff

  • @AmazingVideos-qf5ed
    @AmazingVideos-qf5ed 4 года назад +1

    You're explanations are crystal 👍

  • @BahawalTV
    @BahawalTV 4 года назад +3

    Good and well prepared. Thank you!

  • @ДианаЛевченко-ъ1н
    @ДианаЛевченко-ъ1н 2 года назад +1

    A cool tutorial! Thank you a lot!