SELECT on year month only in '2013-Jan' format?

Question

Hi,
is there a way of selecting on year month only in sql when the format of the date passed is '2013-Jan'. I'm not sure at the moment if I have any control of the date format passed so wanted to explore the sql options.
using sql server 2008 r2
thanks,

Answer 1

Since SQL is a database language, we prefer to do look ups and not calculations. They can be optimized while temporal math messes up optimization. A useful idiom is a report period calendar that everyone uses so there is no way to get disagreements
in the DML. The report period table gives a name to a range of dates that is common to the entire enterprise. 
CREATE TABLE Something_Report_Periods
(something_report_name CHAR(10) NOT NULL PRIMARY KEY
   CHECK (something_report_name LIKE <pattern>),
 something_report_start_date DATE NOT NULL,
 something_report_end_date DATE NOT NULL,
  CONSTRAINT date_ordering
    CHECK (something_report_start_date <= something_report_end_date),
etc);
These report periods can overlap or have gaps. I like the MySQL convention of using double zeroes for months and years, That is 'yyyy-mm-00' for a month within a year and 'yyyy-00-00' for the whole year. The advantages are that it will sort with the ISO-8601
data format required by Standard SQL and it is language independent. The pattern for validation is '[12][0-9][0-9][0-9]-00-00' and '[12][0-9][0-9][0-9]-[01][0-9]-00'
--CELKO-- Books in Celko Series for Morgan-Kaufmann Publishing: Analytics and OLAP in SQL / Data and Databases: Concepts in Practice Data / Measurements and Standards in SQL SQL for Smarties / SQL Programming Style / SQL Puzzles and Answers / Thinking in
Sets / Trees and Hierarchies in SQL
Dear Celko,
You replied with this exact same answer, word for word, over three weeks ago. Look further up the thread of replies.
Thanks.