This question already has an answer here:
I created a table with 3 columns ID (Primary key), when (some varchar value), Created_date(timestamp)
Will naming a field with "When" creates any issue?
I have been querying like update table set table.when='$when' where ID='1'
Please suggest
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it's ok as long as you have to use the tableName along with the column name
update `table`
set `table`.when='$when'
where ID='1'
otherwise, wrap it with backticks
update `table`
set `when`='$when'
where ID='1'
Other Link:
if possible don't use names or identifiers which are on the reserved keyword list to avoid problems.