Why does invalid column index appear in sql

Reasons for invalid column index in sql: 1. The placeholder is inconsistent with the number of parameters; 2. SQL splicing error, please note that each [%] must be included with [''], and with the parameters, use [ ||] splicing; 3. Wrong annotation.

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Reason for invalid column index in sql:

It is basically certain that this error is generally caused by low-level mistakes. Please check your sql spelling

Follow the online instructions I looked for the problem pointed out and found that there was no error that was the same as my own. Finally, after removing a comment, it became normal.

I used idea and used ctrl / to add the comment, that is, add -- before sql.

I don’t know why it didn’t take effect, but it became the source of the error.

Record it here to prevent yourself from forgetting. Several other possible spelling errors are as follows

1 .The placeholder is inconsistent with the number of parameters

For example, when there is a placeholder? , but two parameters #{a},#{b} are passed in here,

2.sql splicing error

For example, for fuzzy query condition a Splicing

a like '%'||#{a}||'%'

Note that each % must be enclosed with '', and spliced ​​with parameters using ||

Of course you can also write a like CONCAT(CONCAT('%', #{a}), '%')

3. Wrong comment

This is the situation I encountered. I commented out the unused sql through --,

but the comments did not take effect normally, resulting in invalid column indexes. Delete them and it will be fine.

Of course there may be other reasons for this situation

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