提交 68d7ff3f authored 作者: Thomas Mueller's avatar Thomas Mueller

Formatting, javadocs.

上级 b3e01df0
...@@ -1474,9 +1474,9 @@ SET RETENTION_TIME int ...@@ -1474,9 +1474,9 @@ SET RETENTION_TIME int
This property is only used when using the MVStore storage engine. This property is only used when using the MVStore storage engine.
How long to retain old, persisted data, in milliseconds. How long to retain old, persisted data, in milliseconds.
The default is 45000 (45 seconds), 0 means overwrite data as early as possible. The default is 45000 (45 seconds), 0 means overwrite data as early as possible.
It is assumed that a file system and hard disk will flush all write buffers within this time. It is assumed that a file system and hard disk will flush all write buffers within this time.
Using a lower value might be dangerous, unless the file system and hard disk flush the buffers earlier. Using a lower value might be dangerous, unless the file system and hard disk flush the buffers earlier.
To manually flush the buffers, use CHECKPOINT SYNC, To manually flush the buffers, use CHECKPOINT SYNC,
however please note that according to various tests this does not always work as expected however please note that according to various tests this does not always work as expected
depending on the operating system and hardware. depending on the operating system and hardware.
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...@@ -22,14 +22,14 @@ Change Log ...@@ -22,14 +22,14 @@ Change Log
replacement string was invalid. replacement string was invalid.
</li><li>A checkpoint is now done every MAX_LOG_SIZE / 2 instead of every </li><li>A checkpoint is now done every MAX_LOG_SIZE / 2 instead of every
MAX_LOG_SIZE, so that the transaction log doesn't grow as large. MAX_LOG_SIZE, so that the transaction log doesn't grow as large.
</li><li>MVStore table engine: new setting "retention_time" to configure the </li><li>MVStore table engine: new setting "retention_time" to configure the
time to retain old data. The default is 45 seconds. time to retain old data. The default is 45 seconds.
</li><li>The method TableEngine.createTable() now returns a Table object. </li><li>The method TableEngine.createTable() now returns a Table object.
</li><li>For read-only databases, for the trace level "debug", </li><li>For read-only databases, for the trace level "debug",
the trace info is written to the temp directory. the trace info is written to the temp directory.
</li><li>Closing the file lock will now wait until the background thread is stopped. </li><li>Closing the file lock will now wait until the background thread is stopped.
</li><li>In version 1.3.172, a performance regression was introduced when </li><li>In version 1.3.172, a performance regression was introduced when
fixing the issue 389 (when there is a multi-column primary key, fixing the issue 389 (when there is a multi-column primary key,
H2 does not seem to always pick the right index). This was related to H2 does not seem to always pick the right index). This was related to
boosting an index that matches the "order by" column list boosting an index that matches the "order by" column list
(the wrong index was used in some cases). (the wrong index was used in some cases).
...@@ -50,8 +50,8 @@ Change Log ...@@ -50,8 +50,8 @@ Change Log
</li><li>Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue </li><li>Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue
sessions are creating large transactions. sessions are creating large transactions.
</li><li>Some small fixes to the GEOMETRY support, patches by Nicolas Fortin. </li><li>Some small fixes to the GEOMETRY support, patches by Nicolas Fortin.
</li><li>When the H2 parser fails to parse a SQL statement, throw a more specific exception that </li><li>The BNF tool and the autocomplete feature are exported in OSGi,
contains extra information to make it possible for smart editors to do autocomplete. Patch from Nicolas Fortin. which makes it possible for smart editors to do autocomplete. Patch from Nicolas Fortin.
</li><li>Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies. </li><li>Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies.
</li><li>Session-temporary LOB's could sometimes accumulate, increasing the size of the DB file until shutdown. </li><li>Session-temporary LOB's could sometimes accumulate, increasing the size of the DB file until shutdown.
Now they are cleared out at every commit. Now they are cleared out at every commit.
......
...@@ -450,13 +450,11 @@ This is work in progress. To try it out, append ...@@ -450,13 +450,11 @@ This is work in progress. To try it out, append
<code>;MV_STORE=TRUE</code> <code>;MV_STORE=TRUE</code>
to the database URL. In general, functionality and performance should be to the database URL. In general, functionality and performance should be
similar than the current default storage engine (the page store). similar than the current default storage engine (the page store).
There are a few features that have not been implemented yet or are not complete: There are a few features that have not been implemented yet or are not complete,
for example there is still a file named <code>.h2.db</code>,
and the <code>.lock.db</code> file is still used to lock a database
(long term, the plan is to no longer use those files).
</p> </p>
<ul><li>There is still a file <code>.h2.db</code>,
and the <code>.lock.db</code> file is still used to lock a database
(long term, the plan is to no longer use those files).
</li><li>The database file(s) sometimes do not shrink as expected.
</li></ul>
<h2 id="differences">Similar Projects and Differences to Other Storage Engines</h2> <h2 id="differences">Similar Projects and Differences to Other Storage Engines</h2>
<p> <p>
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...@@ -56,17 +56,17 @@ public class SortOrder implements Comparator<Value[]> { ...@@ -56,17 +56,17 @@ public class SortOrder implements Comparator<Value[]> {
private static final int DEFAULT_NULL_SORT = SysProperties.SORT_NULLS_HIGH ? 1 : -1; private static final int DEFAULT_NULL_SORT = SysProperties.SORT_NULLS_HIGH ? 1 : -1;
private final Database database; private final Database database;
/** /**
* The column indexes of the order by expressions within the query. * The column indexes of the order by expressions within the query.
*/ */
private final int[] queryColumnIndexes; private final int[] queryColumnIndexes;
/** /**
* The sort type bit mask (DESCENDING, NULLS_FIRST, NULLS_LAST). * The sort type bit mask (DESCENDING, NULLS_FIRST, NULLS_LAST).
*/ */
private final int[] sortTypes; private final int[] sortTypes;
/** /**
* The order list. * The order list.
*/ */
...@@ -213,17 +213,17 @@ public class SortOrder implements Comparator<Value[]> { ...@@ -213,17 +213,17 @@ public class SortOrder implements Comparator<Value[]> {
* 0} as the first order by expression (the column "id") is the second * 0} as the first order by expression (the column "id") is the second
* column of the query, and the second order by expression ("name") is the * column of the query, and the second order by expression ("name") is the
* first column of the query. * first column of the query.
* *
* @return the list * @return the list
*/ */
public int[] getQueryColumnIndexes() { public int[] getQueryColumnIndexes() {
return queryColumnIndexes; return queryColumnIndexes;
} }
/** /**
* Get the column for the given table filter, if the sort column is for this * Get the column for the given table filter, if the sort column is for this
* filter. * filter.
* *
* @param index the column index (0, 1,..) * @param index the column index (0, 1,..)
* @param filter the table filter * @param filter the table filter
* @return the column, or null * @return the column, or null
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