Answer / sa123

For good performance Index is required.
Consider the case of a very large table (20,000,000 rows)
to which new records are added daily (usually about 1,000
of them). Every night, you need to report these additions
on an audit trail. Rather than scan the whole table looking
for changes, you will want to use an index over the
TRANSACTION_DATE column. But the index would need to be
huge. This is a case in which your index is over the entire
table, although you are actually interested only in the
1,000 or so records that were added today. The actual index
is physically many times larger than it needs to be, and it
uses many more disk I/Os to traverse the binary tree to the
leaf data.

Answer / samar singh

Index by tables are composed of two components
1)primary key of binary_interger
2)column of scalar or record type

and used for increasing the size dynamically.

Answer / opulentus

opulentus

Define sql delete statement.

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how to use in conditions? : Sql dba

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take one table is t1 and in that column name is f1 f1 column values are 200 5000 3000 7000 300 600 100 400 800 400 i want display the values asc and desc in a single output. sample output is f1.a 100 200 300 400 500 600 etc...... and f1.d is 5000 4000 3000 2000 1000 etc...

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What is difference between pls_integer and integer?

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What is the difference between UNIQUE CONSTRAINT and PRIMARY KEY? 1. There is no difference. 2. A PRIMARY KEY cannot be declared on multiple columns. 3. A UNIQUE CONSTRAINT cannot be declared on multiple columns. 4. A table can have multiple PRIMARY KEYS but only one UNIQUE CONSTRAINT. 5. A table can have multiple UNIQUE CONSTRAINTs but only one PRIMARY KEY.

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what is ref cursor in pl/sql?

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Explain the update statement in sql

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What is the difference between python and sql?

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3. Select sum(a) sum_1,max(a) max_1 ,count(a) count_1 from ( ( select 1 a from dual union all Select to_number(‘2011’) a from dual union all select 1 a from dual) union select 2 b from dual);

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how to analyze tables with 'mysqlcheck'? : Sql dba

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what is a foreign key ? : Sql dba

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What is sql exception?

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