Multiple duplicate names in the database to go heavy

2015-12-14

When you make a TextBox drop-down box, you need to display the kind of messages stored in the database. But because the same message is constantly in the insert, so caused by the name of a bad fetch message.

For example a scheme has B and c two messages, and both messages are always inserted, but the insertion time is not the same, then there are two ways:

One: Only the names of the B and C messages are taken out. You can use the select DISTINCT name from table

Two: Not only to take out the name but also to calculate and the like can be used with select Name,sum (ID) from table group by name;

Select name, ID from table group by name;--This sentence takes out the last record ID for each message

Multiple duplicate names in the database to go heavy