Tutorial: Quickstart - Revision history

Tuukka Lehtonen: /* Writing the database */

2011-09-03T19:43:52Z

Writing the database

← Older revision		Revision as of 19:43, 3 September 2011
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	// Give the library a name		// Give the library a name
	graph.~~claimValue~~(library, b.HasName, "New Library");		graph.claimLiteral(library, b.HasName, "New Library");

	// Attach the library to the specified container		// Attach the library to the specified container

Tuukka Lehtonen: /* Simantics Database Properties */

2011-09-03T18:35:22Z

Simantics Database Properties

← Older revision		Revision as of 18:35, 3 September 2011
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	:;Core/Layer0 consistency: As an example, a resource ''r'' in the database can be marked an ''InstanceOf'' some type ''t''. In order for ''r'' to be semantically consistent, ''r'' needs to have the properties and relations marked mandatory for it in ''t'' with basic Layer0 requirement specifications. These rules are often fairly simple and easily verifiable. This level of consistency is not ensured by the database server nor the client, but can be considered the responsibility of custom database client query/changeset listeners.		:;Core/Layer0 consistency: As an example, a resource ''r'' in the database can be marked an ''InstanceOf'' some type ''t''. In order for ''r'' to be semantically consistent, ''r'' needs to have the properties and relations marked mandatory for it in ''t'' with basic Layer0 requirement specifications. These rules are often fairly simple and easily verifiable. This level of consistency is not ensured by the database server nor the client, but can be considered the responsibility of custom database client query/changeset listeners.

	:;Domain-specific consistency: A database may contain domain-specific models that may have very complex consistency rules. Such consistencies are meant to be handled through [[SCL Language]] and computing ''issues'' that are presented to the user. For example, some inconsistencies are caused by incomplete models which is a natural situation in the process of developing a model. We simply let the database be domain-specifically inconsistent but strive to make it possible to develop validations that inform the user of such inconsistencies or ''issues''.		:;Domain-specific consistency: A database may contain domain-specific models that may have very complex consistency rules. Such consistencies are meant to be handled through [[org.simantics.scl\|SCL Language]] and computing ''issues'' that are presented to the user. For example, some inconsistencies are caused by incomplete models which is a natural situation in the process of developing a model. We simply let the database be domain-specifically inconsistent but strive to make it possible to develop validations that inform the user of such inconsistencies or ''issues''.

	;Isolation: Simantics DB allows multiple reads or a single write transaction simultaneously, so it should follow this rule.		;Isolation: Simantics DB allows multiple reads or a single write transaction simultaneously, so it should follow this rule.

Juha Kortelainen at 15:54, 28 January 2011

2011-01-28T15:54:09Z

← Older revision		Revision as of 15:54, 28 January 2011
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	{{questionanswer\|'''Q:''' My write transaction was interrupted by unexpected exception. Why am I still seeing parts of the unfinished write operation in my database? What happened to rollback?\|The current DB client implementation does properly support write request rollback, which unfortunately causes the DB client's view of the database to be corrupted. Also if your write operation is not small, even the server's view of the database may be corrupted. At the moment it looks like resolving this issue will be delayed until Simantics 1.2. Until then, the Simantics database cannot be considered for continuous use in any real-life applications.}}		{{questionanswer\|'''Q:''' My write transaction was interrupted by unexpected exception. Why am I still seeing parts of the unfinished write operation in my database? What happened to rollback?\|The current DB client implementation does properly support write request rollback, which unfortunately causes the DB client's view of the database to be corrupted. Also if your write operation is not small, even the server's view of the database may be corrupted. At the moment it looks like resolving this issue will be delayed until Simantics 1.2. Until then, the Simantics database cannot be considered for continuous use in any real-life applications.}}

			[[Category: Database Development]]
			[[Category: Tutorials]]

Tuukka Lehtonen: /* Client opens a database session */

2010-12-03T15:26:34Z

Client opens a database session

← Older revision		Revision as of 15:26, 3 December 2010
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	<syntaxhighlight lang="java">		<syntaxhighlight lang="java">
			import org.simantics.db.Manager;
			import org.simantics.db.ServerAddress;
			import org.simantics.db.Session;

	// Try to load and register the Driver instance with the driver manager		// Try to load and register the Driver instance with the driver manager
	Class.forName("fi.vtt.simantics.procore.ProCoreDriver");		Class.forName("fi.vtt.simantics.procore.ProCoreDriver");

	// Connect to the server at the specified host and credentials.		// Connect to the server at the specified host and credentials.
	Session session = Manager.getSession("procore", ~~InetSocketAddress.createUnresolved~~("localhost", port), username, password);		Session session = Manager.getSession("procore", new ServerAddress("localhost", port), username, password);
	</syntaxhighlight>		</syntaxhighlight>

Tuukka Lehtonen: /* Client opens a database session */

2010-10-14T14:31:10Z

Client opens a database session

← Older revision		Revision as of 14:31, 14 October 2010
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	=== Client opens a database session ===		=== Client opens a database session ===

	To open a client session to a Simantics database server you need to fetch a [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Driver.java\|''Driver'']] ([[javadoc:simantics-head/org/simantics/db/Driver.html javadoc]]) from the [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Manager.java\|''Driver manager'']] ([javadoc:simantics-head/org/simantics/db/Manager.html javadoc]]).		To open a client session to a Simantics database server you need to fetch a [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Driver.java\|''Driver'']] ([[javadoc:simantics-head/org/simantics/db/Driver.html\|javadoc]]) from the [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Manager.java\|''Driver manager'']] ([[javadoc:simantics-head/org/simantics/db/Manager.html\|javadoc]]).

	The basic idea is much the same as in [http://java.sun.com/javase/technologies/database/ JDBC] [http://java.sun.com/javase/6/docs/api/java/sql/Driver.html Driver] and [http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html DriverManager].		The basic idea is much the same as in [http://java.sun.com/javase/technologies/database/ JDBC] [http://java.sun.com/javase/6/docs/api/java/sql/Driver.html Driver] and [http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html DriverManager].

Tuukka Lehtonen: /* Client opens a database session */

2010-10-14T14:30:33Z

Client opens a database session

← Older revision		Revision as of 14:30, 14 October 2010
Line 3:		Line 3:
	=== Client opens a database session ===		=== Client opens a database session ===

	To open a client session to a Simantics database server you need to fetch a [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Driver.java\|''Driver'']] ([[javadoc:simantics-head/org/simantics/db/Driver.html javadoc]) from the [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Manager.java\|''Driver manager'']] ([javadoc:simantics-head/org/simantics/db/Manager.html javadoc]).		To open a client session to a Simantics database server you need to fetch a [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Driver.java\|''Driver'']] ([[javadoc:simantics-head/org/simantics/db/Driver.html javadoc]]) from the [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Manager.java\|''Driver manager'']] ([javadoc:simantics-head/org/simantics/db/Manager.html javadoc]]).

	The basic idea is much the same as in [http://java.sun.com/javase/technologies/database/ JDBC] [http://java.sun.com/javase/6/docs/api/java/sql/Driver.html Driver] and [http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html DriverManager].		The basic idea is much the same as in [http://java.sun.com/javase/technologies/database/ JDBC] [http://java.sun.com/javase/6/docs/api/java/sql/Driver.html Driver] and [http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html DriverManager].

Tuukka Lehtonen: /* Client opens a database session */

2010-10-14T14:30:21Z

Client opens a database session

← Older revision		Revision as of 14:30, 14 October 2010
Line 3:		Line 3:
	=== Client opens a database session ===		=== Client opens a database session ===

	To open a client session to a Simantics database server you need to fetch a [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Driver.java\|''Driver'']] ([~~http~~:~~//www.~~simantics~~.org/hudson/job/javadoc/javadoc~~/org/simantics/db/Driver.html javadoc]) from the [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Manager.java\|''Driver manager'']] ([~~http~~:~~//www.~~simantics~~.org/hudson/job/javadoc/javadoc~~/org/simantics/db/Manager.html javadoc]).		To open a client session to a Simantics database server you need to fetch a [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Driver.java\|''Driver'']] ([[javadoc:simantics-head/org/simantics/db/Driver.html javadoc]) from the [[svn:db/trunk/org.simantics.db/src/org/simantics/db/Manager.java\|''Driver manager'']] ([javadoc:simantics-head/org/simantics/db/Manager.html javadoc]).

	The basic idea is much the same as in [http://java.sun.com/javase/technologies/database/ JDBC] [http://java.sun.com/javase/6/docs/api/java/sql/Driver.html Driver] and [http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html DriverManager].		The basic idea is much the same as in [http://java.sun.com/javase/technologies/database/ JDBC] [http://java.sun.com/javase/6/docs/api/java/sql/Driver.html Driver] and [http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html DriverManager].

Tuukka Lehtonen: /* Simantics Database Properties */

2010-10-14T09:39:33Z

Simantics Database Properties

← Older revision		Revision as of 09:39, 14 October 2010
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	While Simantics DB uses transactions, it does not completely conform to [[wikipedia:ACID\|ACID]] (Atomicity, Consistency, Isolation, Durability) rules:		While Simantics DB uses transactions, it does not completely conform to [[wikipedia:ACID\|ACID]] (Atomicity, Consistency, Isolation, Durability) rules:

	;Atomicity: If something fails during write trasaction, changes are that part of the written data has already gone into the database. ~~Only way to continue~~ is ~~to restart Simantics. This should be fixed~~ in ~~1.2 version~~.		;Atomicity: Atomicity should be covered by checkpoints, journaling, and rollback, but these mechanisms are still under development. Currently, if something fails during write trasaction, changes are that part of the written data has already gone into the database. This work is targeted for the next release and possibly for an in-between service release.

	;Consistency: There are several different levels of consistency in play in Simantics and in its semantic graph database. These are from lowest to highest:		;Consistency: There are several different levels of consistency in play in Simantics and in its semantic graph database. These are from lowest to highest:

Tuukka Lehtonen at 09:20, 14 October 2010

2010-10-14T09:20:03Z

@@ Line 1: / Line 1: @@
 == Quickstart ==
@@ Line 96: / Line 79: @@
 * delete or rename other *.procore files so that you have empty database
 * start server
 == FAQ ==

Tuukka Lehtonen at 09:19, 14 October 2010

2010-10-14T09:19:35Z

← Older revision		Revision as of 09:19, 14 October 2010
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	== Simantics Database Properties =		== Simantics Database Properties ==

	While Simantics DB uses transactions, it does not completely conform to [[wikipedia:ACID\|ACID]] (Atomicity, Consistency, Isolation, Durability) rules:		While Simantics DB uses transactions, it does not completely conform to [[wikipedia:ACID\|ACID]] (Atomicity, Consistency, Isolation, Durability) rules: