Something I find myself doing more and more is checking a string for empty (as in “” or null) and a conditional operator. A current example: s.SiteNumber.IsNullOrEmpty() ? “No Number” : s.SiteNumber; This is just an extension method, it’s equivalent to: string.IsNullOrEmpty(s.SiteNumber) ? “No Number” : s.SiteNumber; Since it’s empty and not null, ?? won’t … Read more
I have two string columns a and b in a table foo. select a, b from foo returns values a and b. However, concatenation of a and b does not work. I tried : select a || b from foo and select a||’, ‘||b from foo Update from comments: both columns are type character(2). 8 … Read more
Are there non obvious differences between NVL and Coalesce in Oracle? The obvious differences are that coalesce will return the first non null item in its parameter list whereas nvl only takes two parameters and returns the first if it is not null, otherwise it returns the second. It seems that NVL may just be … Read more
What is best way to check if value is null or empty string in Postgres sql statements? Value can be long expression so it is preferable that it is written only once in check. Currently I’m using: coalesce( trim(stringexpression),”)=” But it looks a bit ugly. stringexpression may be char(n) column or expression containing char(n) columns … Read more
