Comparison of open source database systems

Comparison of open source database systems
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Derby
Http://db.apache.org/derby/
[JDK 6 comes with a database, and IBM donated it to Apache]
Derby can work in [embedded] mode, or in full [Client/Server mode ].
100% JAVA Implementation
100% Java type 4 JDBC driver
The sql92e standard supports most SQL 99 features.
Acid fully supports independent transactions
J2EE supports JNDI, connection pool, and XA
Views, temporary tables, and storage
Blob and clob Data Types
Row and table locking
Valuable basic query optimization
Server-side indication Constraints
Triggers and stored procedures
Store Java code in the database for server-side functions, triggers, stored procedures, and other operations
Exclude read-only databases in the CD-ROM
Data Import and Export
Quick database encryption options

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H2
Http://www.h2database.com
[Database implementation with the best performance of 100% Java]
The best performance and the most powerful database H2
(1) low performance

(2) Both the online version and the embedded version are supported, and the memory version is also provided.

(3) It has good compatibility and supports equivalent [standard SQL standards] (in fact, there is no database that can 100% comply with the standards)

(4) [provides a very friendly Web-based database management interface]

(5) support for hibernate
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Sqllite [sharpplus SQLite developer]

1. Acid transactions
2. Zero Configuration-no installation or configuration management required
3. A complete database stored in a single disk file
4. database files can be freely shared among machines with different byte sequences.
5. Support database size to 2 TB
6. Small enough, roughly 30 thousand lines of C code, 250 K
7. faster operations than some popular databases in most common databases
8. Simple and Easy APIs
9. Includes TCL binding and supports binding in other languages through wrapper.
10. Source Code with good comments and more than 90% test coverage
11. Independence: no additional dependencies
12. [source is completely open. You can use it for any purpose, including selling it]
13. Support for multiple development languages: C, PHP, Perl, Java, ASP. NET, and Python

Event support
No configuration required, no installation or administrator
[Support most sql92]
A complete database is saved in a file on the disk.
The same database file can be used on different machines.
[Up to 2 TB support for databases]
Character and blob support is limited to available memory only
The entire system has less than 30 thousand lines of code and less than KB of memory (GCC)
[Most applications are faster than common Client/Server databases]
No other Dependencies
Open source code. Code 95% has better comments.
Simple and Easy-to-use API. The official version is compiled with TCL. Others provided separately

[PHP has compiled SQLite by default since 5.x]

SQLite SQL has largely implemented the ANSI sql92 standard. special SQLite supports views, triggers, transactions, and nested SQL. these will be discussed in the following application process. Therefore, we will put them down for the moment, but mainly talk about some SQL statements not supported by SQLite.

1. exists is not supported, although in (in is a case of exists) is supported)

2. Multiple databases are not supported, such as: Create Table db1.table1 as select * From db2.table1;

3. stored procedures are not supported

4. Alter view, trigger, and table are not supported.

5. truncate is not supported. In SQLite, delete has the same effect as truncate without the WHERE clause.

6. The floor and ceiling functions are not supported. There are many other functions.

7. There is no auto increment field, but SQLite actually supports auto increment, that is, when this field is set to "integer primary key.

8. If exists is not supported

SQLite provides support for transaction. The application transaction ensures data integrity and increases the running speed because multiple statements are submitted to the database faster than one.

SQLite cannot directly store binary data. However, you can convert binary data into ASCII code before saving it. Base64 encoding is the most common method to convert binary data into ASCII encoding. The base64 encoding function is provided in the C language code encode. C of SQLite. For Java, you can find a base64 encoding example in the Apache xml rpc project provided in link 6.

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HSQLDB
[Integrated with OpenOffice.org 2.0]
HSQLDB is an open-source Java database,
It has standard SQL syntax and Java interfaces,
It has three modes: SERVER mode, in-process mode, and memory-only mode.
HSQLDB has the following features:

Is an open-source Java Database

Standard SQL syntax and Java Interfaces

HSQLDB can be freely used and distributed

Very concise and fast

[With Memory Database, independent database and C/S database]

[But used in applet]

More details:

Indexes can be created and automatically used.

Support Transaction Processing

Allow table join

Integrity references and constraints

[Supports Java stored procedures and functions]

The database can generate SQL scripts

Use user name, password, access permission, and other security mechanisms
 
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Oracle Berkeley DB
It is a classic C-library toolkit,
[Embedded (embedded )]
Berkeley dB provides practical API interfaces for many programming languages, including C, C ++, Java, Perl, TCL, Python, and PHP.
It can be used to manage up to TB of data, and its performance in many aspects can also compete with commercial database systems.
The total capacity is limited to 256 TB, with a single capacity of 4 GB. Poor network support.

Bdb databases are different from other databases-relational databases, object-oriented databases, and network database, which are embedded (embeded databases) database.

The following describes the differences between bdb and several other databases:
(1) almost all of them use the Structured Query Language (SQL) without exception, while bdb does not.
(2) almost all of them use the customer/server model without exception, while bdb uses the embedded model.
Although Berkeley dB is an open-source product, it is not free and expensive for commercial applications under certain conditions.