what is meant by Hot amp?
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Answer / guest
HOT AMP is a condition when data is NOT EQUALLY DISTRIBUTED
among AMPS and all the data is present in one or few AMPs.
In that case , when user fires SELECT query ,only the
processing power of one or few AMPs among many AMPs will be
used while others AMPS will be IDLE leading to the condition
called HOT AMPs in DB.
In case of HOT AMPs , query performance is very POOR.
Teradata Developer must try to choose PI in such a way that
uniquely distributes the data among AMPs and not lead to HOT
AMPs in Teradata Server.
| Is This Answer Correct ? | 13 Yes | 0 No |
Answer / tdguy
highly non unique PI values, more number of null values can
create a hot amp condition., which means one or more amps
will be holding more rows than other amps. Distribution
occurs unevenly. This can cause out of spool space error.
| Is This Answer Correct ? | 5 Yes | 1 No |
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