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Is There a Limit on the Number of Characters That Can Be Used to Create Column Names in MySQL?


Last Update: 2018/11/07

Yes, there is. For the limitations according to MySQL, refer to the table below.

ComponentMaximum Size
Columns Per Table4096
Row Size65535 Bytes

Note: The amount of space that is used depends on the character set that is used. For example, UTF-8 consumes 3 bytes per character. As such, 255 characters will take up 765 bytes. If every column is this size, then only 85 columns can be generated. For more information, refer to MySQL Developer Zone. Unfortunately, problems with column names and character counts will not be detected when the table is created. Errors will be returned as a query failure when the DataLogger project goes into Runtime. The error "Unable to query recordset on Log Group 'KT' (Reason: 'sp_cursor: The value of the parameter 'value' is invalid')" will be returned. To resolve this error, recreate the table and edit the automatically-generated column names. Then, map the server to the new columns.

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