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diff --git a/documentation/sqlcontainer/sqlcontainer-getting-started.asciidoc b/documentation/sqlcontainer/sqlcontainer-getting-started.asciidoc deleted file mode 100644 index acecb4dc5e..0000000000 --- a/documentation/sqlcontainer/sqlcontainer-getting-started.asciidoc +++ /dev/null @@ -1,85 +0,0 @@ ---- -title: Getting Started with SQLContainer -order: 2 -layout: page ---- - -[[sqlcontainer.getting-started]] -= Getting Started with SQLContainer - -Getting development going with the SQLContainer is easy and quite -straight-forward. The purpose of this section is to describe how to create the -required resources and how to fetch data from and write data to a database table -attached to the container. - -[[sqlcontainer.getting-started.connection-pool]] -== Creating a connection pool - -First, we need to create a connection pool to allow the SQLContainer to connect -to a database. Here we will use the [classname]#SimpleJDBCConnectionPool#, which -is a basic implementation of connection pooling with JDBC data sources. In the -following code, we create a connection pool that uses the HSQLDB driver together -with an in-memory database. The initial amount of connections is 2 and the -maximum amount is set at 5. Note that the database driver, connection url, -username, and password parameters will vary depending on the database you are -using. - - ----- -JDBCConnectionPool pool = new SimpleJDBCConnectionPool( - "org.hsqldb.jdbc.JDBCDriver", - "jdbc:hsqldb:mem:sqlcontainer", "SA", "", 2, 5); ----- - - -[[sqlcontainer.getting-started.query-delegate]] -== Creating the [classname]#TableQuery# Query Delegate - -After the connection pool is created, we'll need a query delegate for the -SQLContainer. The simplest way to create one is by using the built-in -[classname]#TableQuery# class. The [classname]#TableQuery# delegate provides -access to a defined database table and supports reading and writing data -out-of-the-box. The primary key(s) of the table may be anything that the -database engine supports, and are found automatically by querying the database -when a new [classname]#TableQuery# is instantiated. We create the -[classname]#TableQuery# with the following statement: - - ----- -TableQuery tq = new TableQuery("tablename", connectionPool); ----- - -In order to allow writes from several user sessions concurrently, we must set a -version column to the [classname]#TableQuery# as well. The version column is an -integer- or timestamp-typed column which will either be incremented or set to -the current time on each modification of the row. [classname]#TableQuery# -assumes that the database will take care of updating the version column; it just -makes sure the column value is correct before updating a row. If another user -has changed the row and the version number in the database does not match the -version number in memory, an [classname]#OptimisticLockException# is thrown and -you can recover by refreshing the container and allow the user to merge the -data. The following code will set the version column: - - ----- -tq.setVersionColumn("OPTLOCK"); ----- - - -[[sqlcontainer.getting-started.container-creation]] -== Creating the Container - -Finally, we may create the container itself. This is as simple as stating: - - ----- -SQLContainer container = new SQLContainer(tq); ----- - -After this statement, the [classname]#SQLContainer# is connected to the table -tablename and is ready to use for example as a data source for a Vaadin -[classname]#Table# or a Vaadin [classname]#Form#. - - - - |