What are the disadvantages of using VARCHAR?
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Answer / s
1.Additional 2 byte length indicator is stored along with
the VARCHAR column.
2.It can potentialy affect the amount of logging when the
row with VARCHAR column is updated.
3. The placement of the VARCHAR column in a DB2 table has
performance impact. DB2 has to calculate the offset of the
the column that occurs after the VARCHAR each time the
column is accessed that increases the CPU consumption.
Atleast 5-15 instructions are executed per column.
| Is This Answer Correct ? | 9 Yes | 0 No |
Answer / vinod babu
Varchar data types have to handle carefully. otherwise high
chances to get -311 error during the process.
| Is This Answer Correct ? | 4 Yes | 2 No |
Answer / s
When updating VARCHAR columns, the row may not fit on the
page anymore and a pointer to the new row is left in the
orginal space. Over time, there will be more relocated rows
that degrades performance.
| Is This Answer Correct ? | 6 Yes | 6 No |
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