[SQL] skip if latter value equal

Hi list, I was wondering if it was possible for a field in SQL query to return NULL if latter value is exactly the same ? - for given ORDER BY clause, I guess. For example, query returns: xxyy 1 4 true xxyy 5 7 true xxyy 21 8 true yyzz 5 1 false yyzz 7 7 false yyzz 8 34 false I'd

Re: [SQL] skip if latter value equal

Hello you can do it simply in new PostgreSQL 8.4. In older version the best way what I know is using a stored procedure, that returns table create or replace function foo() returns setof yourtablename as $$ declare r yourtablename; s yourtablename; result youratblename; first boolean =

Re: [SQL] skip if latter value equal

Thanks a lot. pozdrowienia mk 2009/7/10 Pavel Stehule pavel.steh...@gmail.com Hello you can do it simply in new PostgreSQL 8.4. In older version the best way what I know is using a stored procedure, that returns table create or replace function foo() returns setof yourtablename as $$

[SQL] How update a table within a join efficiently ?

Hi, how would I update a table within a join in a more efficient way? E.g. the folowing case: table_a holds abstract elements. One column represents priority which can be based on information of other tables. table_b might hold such details in a column size for about 3000 of 8 records out

Re: [SQL] How update a table within a join efficiently ?

2009/7/10 Andreas maps...@gmx.net: Hi, how would I update a table within a join in a more efficient way? E.g. the folowing case: table_a holds abstract elements. One column represents priority which can be based on information of other tables. table_b might hold such details in a column

[SQL] WITH RECURSION output ordering with trees

Hi, I'm playing with the new WITH RECURSIVE feature of 8.4. I'm trying to figure out how to use it with trees. Here is the test code I use: - --DROP TABLE recursion; CREATE TABLE recursion ( id serial, lookup varchar(16), parent_id

Re: [SQL] WITH RECURSION output ordering with trees

pgsql-sql-ow...@postgresql.org wrote: Hi, I'm playing with the new WITH RECURSIVE feature of 8.4. I'm trying to figure out how to use it with trees. Here is the test code I use: - --DROP TABLE recursion; CREATE TABLE recursion

Re: [SQL] WITH RECURSION output ordering with trees

Philippe Lang, 10.07.2009 11:10: Hi, I'm playing with the new WITH RECURSIVE feature of 8.4. I'm trying to figure out how to use it with trees. Here is the test code I use: I'd like to perform a real recursion, and show the tree structure in a more appopriate way, like this: Any idea how to

Re: [SQL] WITH RECURSION output ordering with trees

pgsql-sql-ow...@postgresql.org wrote: Philippe Lang, 10.07.2009 11:10: Hi, I'm playing with the new WITH RECURSIVE feature of 8.4. I'm trying to figure out how to use it with trees. Here is the test code I use: I'd like to perform a real recursion, and show the tree structure in a

Re: [SQL] WITH RECURSION output ordering with trees

In article e6a0649f1fbfa3408a37f505400e7ac215c...@email.attiksystem.ch, Philippe Lang philippe.l...@attiksystem.ch writes: Thanks for your answer. Si there a built-in function that would allow generating the sort path based on the value of the lookup column, instead of the id, which has no

Re: [SQL] WITH RECURSION output ordering with trees

pgsql-sql-ow...@postgresql.org wrote: In article e6a0649f1fbfa3408a37f505400e7ac215c...@email.attiksystem.ch, Philippe Lang philippe.l...@attiksystem.ch writes: Thanks for your answer. Si there a built-in function that would allow generating the sort path based on the value of the lookup