i "discovered" it as a result of typo :) we usually select expressions without tables eg select 1+2 ; etc and the results are as expected, somehow i failed to stretch the analogy to count(*) which is mostly used over tables or table expression.
thanks anyways. regds mallah. On Wed, Mar 9, 2011 at 11:20 PM, Bill Moran <wmo...@potentialtech.com>wrote: > In response to Rajesh Kumar Mallah <mallah.raj...@gmail.com>: > > > Dear List , > > > > if we simply do select count(*) and not specify any table then it gives 1 > > eg: > > > > bric=# SELECT count(*) from job ; > > count > > ------- > > 2380 > > (1 row) > > > > bric=# SELECT count(*) job ; > > job > > ----- > > 1 > > (1 row) > > > > > > > > bric=# SELECT count(*) ; > > count > > ------- > > 1 > > (1 row) > > > > > > > > bric=# SELECT count(*) job_non_exist ; > > job_non_exist > > --------------- > > 1 > > (1 row) > > > > bric=# SELECT count(*) jo1b ; > > jo1b > > ------ > > 1 > > (1 row) > > > > bric=# SELECT count(*) none ; > > ERROR: syntax error at or near "none" > > LINE 1: SELECT count(*) none ; > > > > > > I fail to see any progression ? > > When you don't specify a FROM clause, you get 1 because it's > returning 1 row. No matter what you alias the result to, it's not going > to change the result, unless of course you try to alias it to an SQL > reserved word, such as "none", without quoting it. Of course, if you > include the optional AS, it probably makes more sense what's going on: > > SELECT count(*) AS jolb; > SELECT count(*) AS none; > SELECT count(*) AS "none"; > > -- > Bill Moran > http://www.potentialtech.com > http://people.collaborativefusion.com/~wmoran/ >
