resetDBDirMeta

Syntax

resetDBDirMeta(dbDir)

Arguments

dbDir is a string in the format of "volumeB/DATABASE", indicating the destination directory to which the database will be moved.

Details

When transferring metadata across disk volumes, please call resetDBDirMeta to change the DATABASE storage path in the metadata to the destination path before transferring the metadata. This command can only be executed on the data node.
Note:

  1. The transfer of metadata across volumes can only be performed on the same node;

  2. Before moving the metadata, make sure that there is no writing process on the current node, all transactions have been completed, and all buffers have been synchronized to the disk.

The procedures to move the metalog (including CHUNK_METADATA, DATABASE, IOTRAN_TYPE and LOG) from volume A to volume B are as follows:

  1. Execute command resetDBDirMeta('volumeB/DATABASE') and shut down the server.

  2. Copy the directories CHUNK_METADATA, DATABASE, IOTRAN_TYPE and LOG from VolumeA to VolumeB.

  3. Delete the original directories CHUNK_METADATA, DATABASE, IOTRAN_TYPE and LOG from VolumeA.

  4. Modify the configuration parameter chunkMetaDir = volumeB/CHUNK_METADATA and start the server.