Matlab select query incorrectly handling null

Question

Allan Brett 2021-2-16

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/747477-matlab-select-query-incorrectly-handling-null

评论： Walter Roberson 2024-5-3

Running a simple mysql select query (select * from table) using the SELECT(CONN,QUERY) command. If I run the query through the command line I can view the data as expected. There are a few columns where every value is null which is correct for the data. If I run the query through the Matlab select command all row columns except one return as expected. One column instead of reading all NULL as it should, returns all -2147483648. Any help is appreciated.

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Answer 1

Allan Brett 2021-2-17

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https://ww2.mathworks.cn/matlabcentral/answers/747477-matlab-select-query-incorrectly-handling-null#answer_625932

For those who run into this problem.

https://www.mathworks.com/help/database/ug/select.html

Go to section: Change Missing Values in Imported Data Using Vector Indexing

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Answer 2

Fiza 2024-5-3

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https://ww2.mathworks.cn/matlabcentral/answers/747477-matlab-select-query-incorrectly-handling-null#answer_1451716

编辑：Walter Roberson 2024-5-3

在 MATLAB Online 中打开

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