Query for dates using the CONVERT function in SQL

Function
Once encountered such a situation, in the Database meeting table has publishtime (datetime,8) field, used to store a session, in the deposit due to specify the time of the meeting, the format is Yyyy-mm-dd Hh:mm:ss, And we query it through YYYY-MM-DD, that is, to query all meeting information for a particular day, so that if the select * from meeting where Publishtime= @PublishTime ( Parameter @publishtime is YYYY-MM-DD format) statement query will not get the correct results, such as we want to query the December 1, 2004 meeting information, in the input of 2004-12-01 can not get the results of the query, and this query does not require the input of specific HH: Mm:ss.

At this point we need to use the CONVERT function, which converts an expression of one data type to an expression of another data type. Here we first convert the datetime type in the database to the char type, and since the input parameter is 10 bits, write

SELECT * from meeting where CONVERT (varchar (), publishtime,121) = @PublishTime, This will automatically convert the information in the database to the 10-bit character in the YYYY-MM-DD format after the database gets the parameters in the query. Returns the query results as long as the parameters are the same. and 121 of Convert is the 4-bit year that includes the century digits when converting a datetime type to a char type
These are the small difficulties I encountered in the development of the summary, if the written there is not the right place to welcome everyone to advise!