Schema Export

1. Overview

The schema export tool export-schema.sh/bat is located in the tools directory. It can export schema from a specified database in IoTDB to a script file.

2. Detailed Functionality

2.1 Parameter

Short Param	Full Param	Description	Required	Default
-h	-- host	Hostname	No	127.0.0.1
-p	--port	Port number	No	6667
-u	--username	Username	No	root
-pw	--password	Password	No	root
-sql_dialect	--sql_dialect	Specifies whether the server usestree model ortable model	No	tree
-db	--database	Target database to export (only applies when-sql_dialect=table)	Required if-sql_dialect=table	-
-table	--table	Target table to export (only applies when-sql_dialect=table)	No	-
-t	--target	Output directory (created if it doesn't exist)	Yes
-path	--path_pattern	Path pattern for metadata export	Required if-sql_dialect=tree
-pfn	--prefix_file_name	Output filename prefix	No	dump_dbname.sql
-lpf	--lines_per_file	Maximum lines per dump file (only applies when-sql_dialect=tree)	No	10000
-timeout	--query_timeout	Query timeout in milliseconds (-1= no timeout)	No	-1Range：-1 to Long. max=9223372036854775807
-help	--help	Display help information	No

2.2 Command

Shell
# Unix/OS X
> tools/export-schema.sh [-sql_dialect<sql_dialect>] -db<database> -table<table>  
                [-h <host>] [-p <port>] [-u <username>] [-pw <password>] 
                -t <target_directory> [-path <exportPathPattern>] [-pfn <prefix_file_name>] 
                [-lpf <lines_per_file>] [-timeout <query_timeout>]
# Windows
# Before version V2.0.4.x  
> tools\export-schema.bat [-sql_dialect<sql_dialect>] -db<database> -table<table>  
                [-h <host>] [-p <port>] [-u <username>] [-pw <password>] 
                -t <target_directory> [-path <exportPathPattern>] [-pfn <prefix_file_name>] 
                [-lpf <lines_per_file>] [-timeout <query_timeout>]
                
# V2.0.4.x and later versions
> tools\windows\schema\export-schema.bat [-sql_dialect<sql_dialect>] -db<database> -table<table>  
                [-h <host>] [-p <port>] [-u <username>] [-pw <password>] 
                -t <target_directory> [-path <exportPathPattern>] [-pfn <prefix_file_name>] 
                [-lpf <lines_per_file>] [-timeout <query_timeout>]

2.3 Examples

# Export schema under root.treedb
./export-schema.sh -sql_dialect tree -t /home/ -path "root.treedb.**"

# Output
Timeseries,Alias,DataType,Encoding,Compression
root.treedb.device.temperature,,DOUBLE,GORILLA,LZ4
root.treedb.device.humidity,,DOUBLE,GORILLA,LZ4