PostgreSQL column 'foo' does not exist

Question

I have a table that has 20 integer columns and 1 text column named 'foo'

If I run query:

SELECT * from table_name where foo is NULL 

I get error:

ERROR:  column "foo" does not exist 

I have checked myself that his column indeed exists. If I do something like:

SELECT * from table_name where count is NULL 

The resulting output shows 'foo' as one of the columns.... I am guessing I have to do something special in the query because foo is a text column...

Thanks for the help (POSTGRESQL 8.3)

Answer 1

You accidentally created the column name with a trailing space and presumably phpPGadmin created the column name with double quotes around it:

create table your_table (     "foo " -- ... ) 

That would give you a column that looked like it was called foo everywhere but you'd have to double quote it and include the space whenever you use it:

select ... from your_table where "foo " is not null 

The best practice is to use lower case unquoted column names with PostgreSQL. There should be a setting in phpPGadmin somewhere that will tell it to not quote identifiers (such as table and column names) but alas, I don't use phpPGadmin so I don't where that setting is (or even if it exists).

Answer 2

If for some reason you have created a mixed-case or upper-case column name, you need to quote it, or get this error:

test=> create table moo("FOO" int); CREATE TABLE test=> select * from moo;  FOO  ----- (0 rows) test=> select "foo" from moo; ERROR:  column "foo" does not exist LINE 1: select "foo" from moo;                ^ test=> _ 

Note how the error message gives the case in quotes.