Access Application Notes < two >

Application Notes about Access

20140822

The basic completion of Access database construction, and try to check the weight, do not match the project search, and upload new data and other functions, good performance.

Record the SQL statements that are currently being researched:

1) Remove Duplicates

Select Distinct [Field]

2) Select Duplicates

GROUP by field, field

Having ((field)) >1) and ((Count (post.[ Postnumber])) (>1));

Note the application of parentheses here

Having (() and ())

Also, if used in Access, automatically takes count (field)

3) Naming rules for fields in Access

table. [Field name]

4) about the left connection right inside access

Personal feeling, access inside the relationship menu operation is better. It's much better than the handwriting code.

Anyway, it's a

Left Join

The difference between right and right joins.

Then continue to refine the database.

Since this database has been available, the efficiency of output data has been greatly improved. Originally a region may be 29M in size, now add up to 4 regions, Excel raw data as long as 9M.

The power of technology is great.

To improve work efficiency, the first to improve technology and ideas is a better shortcut.

Access Application Notes < two >