MVStoreTool

java.lang.Object
- org.h2.mvstore.MVStoreTool

```
public class MVStoreTool
extends java.lang.Object
```
Utility methods used in combination with the MVStore.

Field Summary

Fields
Modifier and Type Field Description

static int MAX_NB_FILE_HEADERS_PER_FILE

Constructor Summary

Constructors
Constructor Description

MVStoreTool()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static void`	`compact(java.lang.String fileName, boolean compress)`	Compress the store by creating a new file and copying the live pages there.
`static void`	`compactCleanUp(java.lang.String fileName)`	Clean up if needed, in a case a compact operation was interrupted due to killing the process or a power failure.
`static void`	`dump(java.lang.String fileName, boolean details)`	Read the contents of the file and write them to system out.
`static void`	`dump(java.lang.String fileName, java.io.Writer writer, boolean details)`	Read the contents of the file and display them in a human-readable format.
`static void`	`info(java.lang.String fileName)`	Read the summary information of the file and write them to system out.
`static java.lang.String`	`info(java.lang.String fileName, java.io.Writer writer)`	Read the summary information of the file and write them to system out.
`static void`	`main(java.lang.String... args)`	Runs this tool.
`static void`	`moveAtomicReplace(java.lang.String sourceName, java.lang.String destinationName)`	Rename a file(s) of the named store, and try to atomically replace an existing file(s) of another store.
`static void`	`repair(java.lang.String fileName)`	Repair a store by rolling back to the newest good version.
`static long`	`rollback(java.lang.String fileName, long targetVersion, java.io.Writer writer)`	Roll back to a given revision into a file called *.temp.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail
- MAX_NB_FILE_HEADERS_PER_FILE
```
public static final int MAX_NB_FILE_HEADERS_PER_FILE
```
  See Also:
  
  Constant Field Values

Constructor Detail
- MVStoreTool
```
public MVStoreTool()
```

Method Detail

main

public static void main(java.lang.String... args)

Runs this tool. Options are case-sensitive. Supported options are:

Command line options
[-dump <fileName>]	Dump the contends of the file
[-info <fileName>]	Get summary information about a file
[-compact <fileName>]	Compact a store
[-compress <fileName>]	Compact a store with compression enabled

Parameters:: args - the command line arguments

dump
```
public static void dump(java.lang.String fileName,
                        boolean details)
```
Read the contents of the file and write them to system out.

Parameters:

fileName - the name of the file

details - whether to print details

info
```
public static void info(java.lang.String fileName)
```
Read the summary information of the file and write them to system out.

Parameters:

fileName - the name of the file

dump
```
public static void dump(java.lang.String fileName,
                        java.io.Writer writer,
                        boolean details)
```
Read the contents of the file and display them in a human-readable format.

Parameters:

fileName - the name of the file

writer - the print writer

details - print the page details

info
```
public static java.lang.String info(java.lang.String fileName,
                                    java.io.Writer writer)
```
Read the summary information of the file and write them to system out.

Parameters:

fileName - the name of the file

writer - the print writer

Returns:

null if successful (there was no error), otherwise the error message

compact
```
public static void compact(java.lang.String fileName,
                           boolean compress)
```
Compress the store by creating a new file and copying the live pages there. Temporarily, a file with the suffix ".tempFile" is created. This file is then renamed, replacing the original file, if possible. If not, the new file is renamed to ".newFile", then the old file is removed, and the new file is renamed. This might be interrupted, so it's better to compactCleanUp before opening a store, in case this method was used.

Parameters:

fileName - the file name

compress - whether to compress the data

moveAtomicReplace
```
public static void moveAtomicReplace(java.lang.String sourceName,
                                     java.lang.String destinationName)
```
Rename a file(s) of the named store, and try to atomically replace an existing file(s) of another store.

Parameters:

sourceName - the old fully qualified file name of the store

destinationName - the new fully qualified file name of the store

compactCleanUp
```
public static void compactCleanUp(java.lang.String fileName)
```
Clean up if needed, in a case a compact operation was interrupted due to killing the process or a power failure. This will delete temporary files (if any), and in case atomic file replacements were not used, rename the new file.

Parameters:

fileName - the file name

repair
```
public static void repair(java.lang.String fileName)
```
Repair a store by rolling back to the newest good version.

Parameters:

fileName - the file name

rollback
```
public static long rollback(java.lang.String fileName,
                            long targetVersion,
                            java.io.Writer writer)
```
Roll back to a given revision into a file called *.temp.

Parameters:

fileName - the file name

targetVersion - the version to roll back to (Long.MAX_VALUE for the latest version)

writer - the log writer

Returns:

the version rolled back to (-1 if no version)