Re: Is this an Informix bug?

Carsten Haese wrote: > On Tue, 2007-05-08 at 11:26 -0700, Zachi wrote: > >>I had a typo in an SQL query, and I stumbled upon an interesting >>feature/bug. Try this code: >> >>create table tab(a int); >>create table tab1(a int); >>insert into tab values(1); >>insert into tab values(null); >>select count(*) from tab where tab is not null; >>select count(*) from tab where tab is null; >>select count(*) from tab where tab1 is null;>> >>The answers are: >> 2 >> 0 >> SQL Error -217 (column not found) >> >>which behaves as if Informix evaluates tab is null to false, tab is >>not null to true and a different table name is considered an error. Is >>there a documented (or even undocumented) meaning for use of the table >>name in a WHERE clause using IS NULL and IS NOT NULL or is this a bug? IDS 7.31: select sec_desc2 from sec_desc2;SQL -217: Column (sec_desc2) not found in any table in the query (or SLV is undefined). SQLSTATE: IX000 at /dev/stdin:1 IDS 10.00: select sec_desc2 from sec_desc2; -- no output. Art S. Kagel > It's a feature. IDS accepts the name of a table as an expression. This > expression constructs ROW objects on the fly, containing all columns of > the table. Try "select tab from tab" to see what that does. What that's > good for, well, your guess is probably just as good as mine. > > HTH, >