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PostgreSQL Adapter-nexj/schema-test

384 bytes added, 20:49, 26 January 2014
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{{Admon/obsolete}}
 
<big><big> PostgreSQL Adapter for NexJ - Working Inside Schema 'test' </big></big>
{{NexJ_Express Index}}
===1- Initializing the SQL environment===
* ''PostgreSQLAdapter.java''
: When a connection is first established, this initial SQL statement should execute in MySQL, which is not the case for PostgreSQL, so the implementation was removed from PostgreSQLAdapter.java:
: After activating the connection, the database is locked.
===2- Modifying Syntax DATA DEFINITION LANGUAGE _ DDL =====CREATING SCHEMA === * List of Files needed to be modified *:src- [[ PostgreSQL_Adapter-nexj/SchemaManger | PostgreSQLSchemaManager.java ]] --- ([[SchemaBackup]]) // Extends SQLSchemaManager.java - class for reading, creating and upgrading the database schema: test- [[ PostgreSQL_Adapter-nexj/SchemaMangerTest | PostgreSQLSchemaManagerTest.java]] // Extends SQLSchemaManagerTest.java: Script - scripts are being processed through SQLDataTest.java * <u><code> CREATE TABLE </code></u>====: File to configure: ''PostgreSQLSchemaManager.java'':: 1- DATA TYPE: data types are changed in '''''<code> appendColumnType() </code>''''' based on each jdbc type's equivalent in PostgreSQL. :::*[http://db.apache.org/ddlutils/databases/postgresql.html mapping JDBC data types to PostgreSQL data types]:::*[http://en.wikibooks.org/wiki/Converting_MySQL_to_PostgreSQL#Data_Types comparison between Postgre and MySQL data types] :: 2- STORAGE ENGINE: In MySQL, the storage engine is set to a transactional safe engine such as [http://www.wikivs.com/wiki/MySQL_vs_PostgreSQL#MySQL:InnoDB InnoDB], whereas PostgreSQL has a single built in engine. So, implementation of '''''<code> appendTableSuffix() </code>''''' in PostgreSQLManager.java was removed:: 3- CHARACTER SET: In MySQL, the character set should be defined when creating a table. Whereas in PostgreSQL when a database is created, the character set is set to 'UTF8' by default. :: 4- AUTO INCREMENT: PostgreSQL doesn't support 'auto_increment' as some other databases for a unique identifier column. There are two ways around this, 1- To create a 'sequence', 2- Use SERIAL, which is a macro around 'sequence'. SERIAL is an 'integer' and a 'sequence, with the column default to the sequences next value. As of postgreSQL 7.3, to make a serial column unique, it should be specified as a unique constraint or a primary key. More info @ [[PostgreSQL_Adapter-nexj/Resources#Mapping_Data_Types.2C_Metadata | PostgreSQL Resources]]::
<source lang=java>
/* MySQL version of creating table script */
)engine=InnoDB character set = utf8
</source>
::
<source lang=java>
/* PostgreSQL version of creating table script */
</source>
====*<u><code> CREATE TEXT TABLE </code></u>====
:The implementation in '''''<code> crateTextTable() </code>''''' is removed for now (base class's version is being called).
:TODO To be checked if it's the case for PostgreSQL as well.
==== * <u><code>CREATE INDEX </code></u> ====
:The implementation in '''''<code> createIndex() </code>''''' is removed for now (base class's version is being called).
:TODO To be checked if it's the case for PostgreSQL as well.
:Note- If there was a complain for duplicate index name, a fully qualified name can be used. Just note that PostgreSQL doesn't like fully qualified name as <code>table.indexname</code> for indexes or triggers, instead a '_' can be used: <code>table_indexname</code>
==== * <code> <u> CREATE Trigger </u></code>====
:TODO To be checked if triggers are needed for PostgreSQL as well. It's not an abstract method in '''''SQLSchemaManager.java'''''.
: <code>'''''createTrigger()'''''</code> is added to '''''MySQLSchemaManager.java'''''
=== UPDGRADING SCHEMA===* List of Files needed to be modified ==={|class="collapsible collapsed" style="border-style:solid;border-width:thin;bordersrc -color:black"!align="left" style="background-color:SteelBlue; font-weight:bold;border-style:solid;border-width:thin;padding: 2px 2px 2px 2px;"| '''Files to Configure''' |- |:src:: [[ PostgreSQL_Adapter-nexj/Adapter SchemaManger | PostgreSQLAdapterPostgreSQLSchemaManager.java ]] // Extends SQLAdapter.java - SQL Persistence adapter, responsible for regular data queries -- (insert, select, delete):: [[ PostgreSQL_Adapter-nexj/SchemaManger | PostgreSQLSchemaManager.java SchemaBackup]] ) // Extends SQLSchemaManager.java - class for reading, creating and upgrading the database schema:: [[ PostgreSQL_Adapter-nexj/Upgrade | main.upgrade ]]: test- [[ PostgreSQL_Adapter-nexj/SchemaMangerTest | PostgreSQLSchemaManagerTest.java]] // Extends SQLSchemaManagerTest.java:Script - postgresql_drop.sql * <u><code> DROP TABLE </code></u> * <u><code> INSERT INTO TABLE </code></u> * <u><code> ALTER TABLE </code></u> ==3- DATA MANIPULATION LANGUAGE _ DML ==* List of Files needed to be modified[[sampleProj]]: src- [[ PostgreSQL_Adapter-nexj/AdapterTest Adapter | PostgreSQLAdapterTestPostgreSQLAdapter.java ]]] // Extends SQLAdapterTestSQLAdapter.java - SQL Persistence adapter, responsible for regular data queries (insert, select, delete):: test- [[ PostgreSQL_Adapter-nexj/SchemaMangerTest AdapterTest | PostgreSQLSchemaManagerTestPostgreSQLAdapterTest.java]]] // Extends SQLSchemaManagerTestSQLAdapterTest.java
: Script - scripts are being processed through SQLDataTest.java
:: postgresql_setuppostgresql_insert.sql:: TO be cond'|}
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