docs

h2/src/docsrc/html/roadmap.html

@@ -51,6 +51,9 @@ Roadmap
 <h2>Priority 2</h2>
 <ul>
 <li>Automatic mode: jdbc:h2:auto: (embedded mode if possible, if not use server mode). Keep the server running until all have disconnected.
+</li><li>Support function overloading as in Java (multiple functions with the same name, but different parameter count or data types).
+</li><li>Linked tables that point to the same database should share the connection ([SHARED CONNECTION]). Serialize access to the connection.
+</li><li>Linked tables should support a schema name: CREATE LINKED TABLE ... (... [schemaName, ] originalTableString) - DB2: SET SCHEMA after connecting
 </li><li>Support OSGi: http://oscar-osgi.sourceforge.net, http://incubator.apache.org/felix/index.html
 </li><li>Better space re-use in the files after deleting data: shrink the data file without closing the database (if the end of the file is empty)
 </li><li>Full outer joins
@@ -58,10 +61,8 @@ Roadmap
 </li><li>Change LOB mechanism (less files, keep index of lob files, point to files and row, delete unused files earlier, maybe bundle files into a tar file)
 </li><li>Clustering: recovery needs to becomes fully automatic. Global write lock feature.
 </li><li>Option for Java functions: constant/isDeterministic/readonly/pure (always return the same value) to allow early evaluation when all parameters are constant
-</li><li>Support function overloading as in Java (multiple functions with the same name, but different parameter count or data types)
 </li><li>Deferred integrity checking (DEFERRABLE INITIALLY DEFERRED)
 </li><li>Groovy Stored Procedures (http://groovy.codehaus.org/Groovy+SQL)
-</li><li>Linked tables that point to the same database should share the connection ([SHARED])
 </li><li>System table / function: cache usage
 </li><li>Add a migration guide (list differences between databases)
 </li><li>Optimization: automatic index creation suggestion using the trace file?
@@ -361,6 +362,8 @@ Roadmap
 </li><li>HSQLDB compatibility: automatic data type for SUM if value is the value is too big (by default use the same type as the data).
 </li><li>Support hints for the optimizer (which index to use).
 </li><li>Improve the optimizer to select the right index for special cases: where id between 2 and 4 and booleanColumn
+</li><li>H2 Console: new option 'Open a browser when starting the H2 Console'.
+</li><li>Enable warning for 'Local variable declaration hides another field or variable'.
 </li></ul>
 
 <h2>Not Planned</h2>

h2/src/main/org/h2/res/help.csv

@@ -407,9 +407,11 @@ Usually, for update statements, the old rows are deleted first
 and then the new rows inserted. It is possible to emit update
 statements (however this is not possible on rollback), however
 in this case multi-row unique key updates may not always work.
+If a query is used instead of the original table name, the table is read only.
 The current user owner must have admin rights.
 ","
-CREATE LINKED TABLE LINK('org.h2.Driver', 'jdbc:h2:test', 'sa', '', 'TEST')
+CREATE LINKED TABLE LINK('org.h2.Driver', 'jdbc:h2:test2', 'sa', 'sa', 'TEST');
+CREATE LINKED TABLE LINK('', 'jdbc:h2:test2', 'sa', 'sa', '(SELECT * FROM TEST WHERE ID>0)');
 "
 
 "Commands (DDL)","CREATE ROLE","
@@ -1684,7 +1686,7 @@ VARCHAR2 | NVARCHAR | NVARCHAR2 | VARCHAR_CASESENSITIVE}
 Unicode String. Use two single quotes ('') to create a quote.
 There is no maximum precision. The maximum size is the memory available.
 The precision is a size constraint; only the actual data is persisted.
-For large text data CLOB should be used.
+For large text data CLOB should be used; see there for details.
 See also java.lang.String.
 ","
 VARCHAR(255)
@@ -1695,7 +1697,7 @@ VARCHAR_IGNORECASE [( precisionInt )]
 ","
 Same as VARCHAR, but not case sensitive when comparing. Stored in mixed case.
 There is no maximum precision. The maximum size is the memory available.
-For large text data CLOB should be used.
+For large text data CLOB should be used; see there for details.
 ","
 VARCHAR_IGNORECASE
 "
@@ -1708,7 +1710,7 @@ This type is supported for compatibility with other databases and older applicat
 The difference to VARCHAR is that trailing spaces are ignored and not persisted.
 Unicode String. Use two single quotes ('') to create a quote.
 There is no maximum precision. The maximum size is the memory available.
-For large text data CLOB should be used.
+For large text data CLOB should be used; see there for details.
 ","
 CHAR(10)
 "
@@ -1717,7 +1719,7 @@ CHAR(10)
 {BLOB | TINYBLOB | MEDIUMBLOB | LONGBLOB | IMAGE | OID}
 [( precisionInt )]
 ","
-Like BINARY, but intended for very large values.
+Like BINARY, but intended for very large values such as files or images.
 Unlike when using BINARY, large objects are not kept fully in-memory.
 Use PreparedStatement.setBinaryStream to store values.
 ","
@@ -1728,8 +1730,13 @@ BLOB
 {CLOB | TINYTEXT | TEXT | MEDIUMTEXT | LONGTEXT | NTEXT | NCLOB}
 [( precisionInt )]
 ","
-Like VARCHAR, but intended for very large values.
-Unlike when using VARCHAR, large objects are not kept fully in-memory.
+CLOB is like VARCHAR, but intended for very large values.
+Unlike when using VARCHAR, large CLOB objects are not kept fully in-memory.
+CLOB should be used for documents and texts with arbitrary size such as 
+XML or HTML documents, text files, or memo fields of unlimited size.
+VARCHAR should be used for text with relatively short average size (for example 
+shorter than 200 characters). Short CLOBs are stored inline, but there is an 
+overhead compared to VARCHAR. 
 Use PreparedStatement.setCharacterStream to store values.
 ","
 CLOB