hi,
I tried to find the not null elements from database
@genus_counts = Table.count(:all, :conditions=> {:col1 => params[:gm],
:col2
=> nil}, :without => {:col3 => nil})
its not recognising “without” function.
and
@genus_counts = Table.count(:all, :conditions=> {:col1 => params[:gm],
:col3
!= nil :col2 => nil})
its not recognising “!=” operator… Kindly suggest me and correct
above
statement.
–
With Regards
Palani Kannan. K
PalaniKannan K wrote in post #950423:
I tried to find the not null elements from database
@genus_counts = Table.count(:all, :conditions=> {:col1 => params[:gm],
:col2
=> nil}, :without => {:col3 => nil})
In SQL you don’t use equality to find NULL values.
SELECT * FROM my_table WHERE my_col IS NULL;
or
SELECT * FROM my_table WHERE my_col IS NOT NULL;
Rails:
:conditions => [ “col1 = ? and col2 IS NULL and col3 IS NOT NULL”,
params[:gm] ]
Dear All,
@genus_count = Table.count(:all, :conditions => [‘col3 is not null and
col2 is null and col1 = ?’, params[:gm])
<%= @genus_count %>
It works.
–
With Regards,
Palani Kannan. K,
Walter D. wrote in post #954658:
On which database(s)? This is something I have wrestled with before on
SQLite deploying to MySQL. What works on one fails on the other, and
vice-versa.
AFAIK this syntax work fine in both SQLite and MySQL and every other
database backend I’ve used. I believe it is compliant with SQL '92
standard.
On which database(s)? This is something I have wrestled with before on
SQLite deploying to MySQL. What works on one fails on the other, and
vice-versa.
Walter