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# Schema Import

## 1. Overview

The schema import tool `import-schema.sh/bat` is located in `tools` directory.

## 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. Supported for hidden input since V2.0.9-beta                                                                | No       | root                                      |
| `-sql_dialect`  | `--sql_dialect`           | Specifies whether the server uses`tree `model or`table `model            | No      | tree                                      |
| `-db`           | `--database`              | Target database for import                                               | Yes      | -                                         |
| `-table`        | `--table`                 | Target table for import (only applies when`-sql_dialect=table`)          | No      | -                                         |
| `-s`            | `--source`                | Local directory path containing script file(s) to import                 | Yes      |                                           |
| `-fd`           | `--fail_dir`              | Directory to save failed import files                                    | No       |                                           |
| `-lpf`          | `--lines_per_failed_file` | Maximum lines per failed file (only applies when`-sql_dialect=table`)    | No      | 100000Range：`0 to Integer.Max=2147483647` |
| `-help`         | `--help`                  | Display help information                                                 | No       |                                           |
| `-usessl`       | `--use_ssl`               | Use SSL protocol. Supported since V2.0.9-beta                            | No      | -                                    |
| `-ts`           | `--trust_store`           | Trust store. Supports hidden input. Supported since V2.0.9-beta          | No      | -                                    |
| `-tpw`          | `--trust_store_password`  | Trust store password. Supports hidden input. Supported since V2.0.9-beta | No        | -                                    |

### 2.2 Command

```Bash
# Unix/OS X
tools/import-schema.sh [-sql_dialect<sql_dialect>] -db<database> -table<table> 
     [-h <host>] [-p <port>] [-u <username>] [-pw <password>]
       -s <source> [-fd <fail_dir>] [-lpf <lines_per_failed_file>]
      
# Windows
# Before version V2.0.4.x
tools\import-schema.bat [-sql_dialect<sql_dialect>] -db<database> -table<table>  
      [-h <host>] [-p <port>] [-u <username>] [-pw <password>]
       -s <source> [-fd <fail_dir>] [-lpf <lines_per_failed_file>] 
       
# V2.0.4.x and later versions       
tools\windows\schema\import-schema.bat [-sql_dialect<sql_dialect>] -db<database> -table<table>  
      [-h <host>] [-p <port>] [-u <username>] [-pw <password>]
       -s <source> [-fd <fail_dir>] [-lpf <lines_per_failed_file>] 
```

### 2.3 Examples

Import `dump_database1.sql` from `/home` into `database2`,

```sql
-- File content (dump_database1.sql):
DROP TABLE IF EXISTS table1;
CREATE TABLE table1(
        time TIMESTAMP TIME,
        region STRING TAG,
        plant_id STRING TAG,
        device_id STRING TAG,
        model_id STRING ATTRIBUTE,
        maintenance STRING ATTRIBUTE,
        temperature FLOAT FIELD,
        humidity FLOAT FIELD,
        status BOOLEAN FIELD,
        arrival_time TIMESTAMP FIELD
);
DROP TABLE IF EXISTS table2;
CREATE TABLE table2(
        time TIMESTAMP TIME,
        region STRING TAG,
        plant_id STRING TAG,
        device_id STRING TAG,
        model_id STRING ATTRIBUTE,
        maintenance STRING ATTRIBUTE,
        temperature FLOAT FIELD,
        humidity FLOAT FIELD,
        status BOOLEAN FIELD,
        arrival_time TIMESTAMP FIELD
);
```

Executing the command:

```Bash
./import-schema.sh -sql_dialect table -s /home/dump_database1.sql -db database2 

# If database2 doesn't exist
The target database database2 does not exist

# If database2 exists
Import completely!
```

Verification:

```Bash
# Before import
IoTDB:database2> show tables
+---------+-------+
|TableName|TTL(ms)|
+---------+-------+
+---------+-------+
Empty set.

# After import
IoTDB:database2> show tables details
+---------+-------+------+-------+
|TableName|TTL(ms)|Status|Comment|
+---------+-------+------+-------+
|   table2|    INF| USING|   null|
|   table1|    INF| USING|   null|
+---------+-------+------+-------+

IoTDB:database2> desc table1
+------------+---------+---------+
|  ColumnName| DataType| Category|
+------------+---------+---------+
|        time|TIMESTAMP|     TIME|
|      region|   STRING|      TAG|
|    plant_id|   STRING|      TAG|
|   device_id|   STRING|      TAG|
|    model_id|   STRING|ATTRIBUTE|
| maintenance|   STRING|ATTRIBUTE|
| temperature|    FLOAT|    FIELD|
|    humidity|    FLOAT|    FIELD|
|      status|  BOOLEAN|    FIELD|
|arrival_time|TIMESTAMP|    FIELD|
+------------+---------+---------+
 
IoTDB:database2> desc table2
+------------+---------+---------+
|  ColumnName| DataType| Category|
+------------+---------+---------+
|        time|TIMESTAMP|     TIME|
|      region|   STRING|      TAG|
|    plant_id|   STRING|      TAG|
|   device_id|   STRING|      TAG|
|    model_id|   STRING|ATTRIBUTE|
| maintenance|   STRING|ATTRIBUTE|
| temperature|    FLOAT|    FIELD|
|    humidity|    FLOAT|    FIELD|
|      status|  BOOLEAN|    FIELD|
|arrival_time|TIMESTAMP|    FIELD|
+------------+---------+---------+
```