On 04/19/2012 04:55 AM, Dennis wrote:
Hello Tom,
The example you have given is EXACTLY why something like CURRENT is
needed to limit the number of unique queries or prepared statements. (or
to do a selection of all values before an update meaning two executed
queries.)
regards,.
Dennis
On 04/18/2012 06:24 PM, Tom Lane wrote:
Dennis<dennis.verb...@victorem.com> writes:
When a query is written to update a table, the usual process is to
list all the columns that need
updating. This could imply the creation of many possible queries for
many columns. In an effort to
keep the UPDATE queries more uniform, less number of unique queries,
a keyword similar to DEFAULT,
let's say CURRENT, is required to indicate that the current value
must not change.
No it isn't. Just write the name of the column, eg
update mytable set x = x, y =<new value>, z = z where ...
There's no reason to invent nonstandard syntax for this.
regards, tom lane
Not if you have all the old and new values:
update mytable set x= xval, y=yval, z=zval where yval happens to be a
new value and xval, zval are current.
Seems your callers knows which have changed. Does it not know which have
not (and what their values are)?
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