Heaps, Deletes, and Optimistic Isolation Levels
Erik shows that heaps have even more drawbacks under optimistic concurrency.
2018-02-07
2,743 reads
Erik shows that heaps have even more drawbacks under optimistic concurrency.
2018-02-07
2,743 reads
You should stick to using tables in SQL Server, rather than heaps that have no clustered index, unless you have well-considered reasons to choose heaps. However, there are uses for heaps in special circumstances, and it is useful to know what these uses are, and when you should avoid heaps. Uwe Ricken explains, and demonstrates why you'd be unwise to use heaps rather than tables when the data is liable to change.
2016-10-14
3,646 reads
In SQL Server, heaps are rightly treated with suspicion. Although there are rare cases where they perform well, they are likely to be the cause of poor performance. If a table is likely to have a large number of changes, then it can become fragmented due to way that space is allocated and forward pointers used. How does one detect this problem? Is it significant? How does one deal with it, if necessary? Neeraj Tripathi explains.
2015-11-23
3,694 reads
2014-05-21
1,834 reads
When no clustered index is defined on a table, that table is said to be a Heap. Heaps are not ideal when it comes to performance but there are lots of instances where you have heaps.
2013-05-15
3,128 reads
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create table t1 (id int primary key, city varchar(50)); insert into t1 values (1, 'Rome'), (2, 'New York'), (3, NULL);If we execute the following query, how will the records be sorted in both environments?
select city from t1 order by city;See possible answers