column « Performance « JPA Q&A

1. Table name or column name length affect performance?

I'm using MySQL + Hibernate. MySQL table name length and column name length affect application performance ? exmaple)

awd (table)
id int,
awd_nm varchar(...),
tit varchar(...)

award (table)
id int,
award_name varchar(...),
title varchar(...)
which is better ?

2. Performance difference in various Hibernate Queries on VarChar MsSql columns

I have a Query in hibernate which I believe is because of the VARCHAR and NVARCHAR discrepancies in the driver and MsSql discussed here Getting Hibernate and SQL Server to ...

3. Many-to-many with extra column performance issue.

Hi, I have class Document which has many-to-many back to Document. But this association table has extra column. The main class looks like: public class Document { private Long id; private String name; private Set parent = new HashSet(); private Set child = new HashSet(); ... setters/getters } The association class is: public class DocumentRel { private Document parent; private Document ...

4. BLOB column and performance

Hi All, We've blob columns in some of the tables in our design. Few tables can have a maximum of 3 blobs. Is it recommended to move this blob data to a separate table and define one-to-one relationship? If we keep the blob in the same table, will it impact performance everytime i load this table??? Is it possible to lazy-load ...

5. Performance and column aliasing

Hi vij123456, As far I am aware, it is recommended to use table aliases always in Oracle SQLs. Especially if they are used in PL/SQL. However table aliases in simple SQL (having one table) do not affect parsing performance. For SQLs which have multiple tables joined, it is even better performance-wise to use table aliases. Regards, Anton