SQLTeam.com | Weblogs | Forums

"Disk usage by top tables"


#1

Hello,
I'm searching for explain about the table fields .
what is "Record" , " Reserved", "Data" , "Indexes" - what is the meaning of each one?

Screen shot attached , if you can please explain usage of 2 tables . so i'll understand.

thank you


#2

Record: Number of (active) records (rows) in the table
Reserved: Size (in KB) of the table (data+index+unused)
Data: Size (in KB) of the (active) data in the table
Index: Size (in KB) of the index(ex) of the table
Unused: Size (in KB) of the "inactive" data in the table

When inserting ex. 1 mill rows in an empty table, it takes up som space; ex. 500 MB.

Table name  Record     Reserved  Data     Indexes Unused
testtable   1,000,000  500,000   500,000  0       0

If you then delete half, the reserved size will stay the same, data size will decrease and unused will increase.

Table name  Record     Reserved  Data     Indexes Unused
testtable   500,000    500,000   250,000  0       250,000

When inserting data again, it will "eat" from the unused space (unless your table was specified not to reuse unused space).