Update Problem

[jameswoo]

I upgrate to 5.14 today because version 5.11 can't run in windows 98.

But I found something different in 5.11.

When I want to change a column with a string like 'ceiling(msl/8)' in data window, it reports 'unkown column 'msl' in 'field list'. In the history window, it use set column_name=ceiling(msl/8) as the update parameter.

In fact, I don't want to treat the ‘ceiling’ as a function, and in 5.11 it's just save the whole string.

Can anyone tell me how to save this string in a column?

Thank you!

[peterlaursen]

Yes, I can tell.

Please read: http://webyog.com/faq/8_99_en.html

.. so what you need to do is to enclose the literal string in backticks/backquotes like

Code:

`ceiling(msl/8)`

Now watch the HISTORY tab and see what it actually sends to MySQL!

.. but actually nobody ever told me that it now is possible to use functions and have them evaluated. So I guess that I will have to update the FAQ with that.

@Ritesh/Sarat: intended behaviour? It would be 'smart' if it only attempted to evaluate functions that actually exist! It could use the functions-list from 'keywords.db' file !!

[jameswoo]

Well, the problem has been solved now! 😆

Thank you!

[peterlaursen]

Another consideration:

In a numerical field you can use functions like round(7.9,0)

and it sends:

update `tablename1` set `id`=round(7.9,0) … where …

and 8 is inserted as the function is evaluated to 8 by the server.

however you cannot use expressions like 7+3

it sends

update `tablename1` set `id`='7+3' … where …

.. but the server does not evaluate the expression, because it is sent as a string.

What about an Excel-like formula notation (using '=') like '=7+3'

.. so that SQLyog will do

update `tablename1` set `id`=7+3 … where … (no quotes!)

BTW: I think it should be a configuration option to turn on/off evalutation of expressions and functions.

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