Purpose
You can use this statement to import data from an external file.
Notice
- Do not use the
LOAD DATAstatement on tables with triggers. - To import data from an external file, you must have the
FILEprivilege and configure the following settings:- To load files from an OBServer node, you must configure the system variable secure_file_priv to specify the path that can be accessed during file import or export.
- To load local files on a client, you must add the
--local-infile[=1]option when you start the MySQL client or OceanBase Command-Line Client (OBClient), to enable data loading from the local file system.
OceanBase Database supports the following input files for the LOAD DATA statement:
Files on an OBServer node: You can execute the
LOAD DATA INFILEstatement to load data from files on an OBServer node into database tables.Files in the local file system of the client: You can execute the
LOAD DATA LOCAL INFILEstatement to load data from files in the file system of the local client into database tables.Note
Starting from V4.2.2, OceanBase Database in Oracle mode supports the
LOAD DATA LOCAL INFILEsyntax to load local data files.Files in an object storage service system: You can execute the
LOAD DATA REMOTE_OSS INFILEstatement to load data from files in an object storage service system into database tables.
You can use the LOAD DATA statement to import a CSV text file in the following process:
Parse the file: OceanBase Database reads data from a file based on the file name that you enter and determines whether to perform parallel or serial parsing of data from the input file based on the specified degree of parallelism (DOP).
Distribute the data: OceanBase Database is a distributed database. Data of each partition may be distributed across different OBServer nodes. The
LOAD DATAstatement is used to process the parsed data and determine to which OBServer node the data is sent.Insert the data: After the destination OBServer node receives the data, it executes the
INSERTstatement to insert the data into the corresponding partition.
To import data from an external file, you must have the FILE privilege. You can use the GRANT FILE ON *.* TO $user_name; statement to grant the privilege, where $user_name is the user that executes the LOAD DATA statement.
Syntax
LOAD DATA
[ [/*+ PARALLEL(N) load_batch_size(M) APPEND */]
| [/*+ PARALLEL(N) direct(bool, int) */] ]
[REMOTE_OSS | LOCAL] INFILE 'file_name'
INTO TABLE table_name
[{FIELDS | COLUMNS}
[TERMINATED BY 'string']
[[OPTIONALLY] ENCLOSED BY 'char']
[ESCAPED BY 'char']
]
[LINES
[STARTING BY 'string']
[TERMINATED BY 'string']
]
[IGNORE number {LINES | ROWS}]
[(column_name_var
[, column_name_var] ...)]
Parameters
| Parameter | Description |
|---|---|
| parallel(N) | The DOP for loading data. The default value of N is 4. |
| load_batch_size(M) | The batch size of each insertion. The default value of M is 100. Recommended value range: [100,1000]. |
| APPEND | A hint for enabling the direct load feature. This feature allows you to directly allocate space and write data to data files. The APPEND hint is equivalent to direct(true, 0), and can collect statistics online like the GATHER_OPTIMIZER_STATISTICS hint does. |
| direct | A hint for enabling the direct load feature. The bool parameter in direct(bool, int) specifies whether the given CSV file is ordered. The value true indicates that the file is ordered. The int parameter specifies the maximum number of error rows allowed. |
| REMOTE_OSS | LOCAL | Optional. Valid values:
|
| file_name | The path and file name of the file to import. You can specify a value in either of the following formats:
NoteWhen you import a file from an object storage service system, make sure that the following conditions are met:
|
| table_name | The name of the table from which data is imported. Partitioned and non-partitioned tables are supported. |
| FIELDS | COLUMNS | The format of the field.
|
| LINES STARTING BY | The start character of the line. |
| LINES TERMINATED BY | The end character of the line. |
| IGNORES number { LINES | ROWS } | Specifies to ignore the first few lines. LINES indicates the first few lines of the file. ROWS indicates the first few rows of data specified by the field delimiter. By default, fields in the input file are mapped to columns in the destination table one by one. If the input file does not contain all the columns, the missing columns are filled based on the following mappings:
|
| column_name_var | The name of the imported column. |
Examples
Example 1: Import data from a file on an OBServer node
Set a global security path.
Notice
For security reasons, you can connect to the database only through a local socket to execute the SQL statement for setting
secure_file_priv. For more information, see secure_file_priv.obclient> SET GLOBAL secure_file_priv = "/";Log out of the database.
Note
secure_file_privis aGLOBALvariable. Therefore, you need to run\qto exit for the settings to take effect.obclient> \qThe return result is as follows:
ByeConnect to the database again. Execute the
LOAD DATAstatement to import data.Perform normal import.
obclient> LOAD DATA INFILE '/home/admin/test.csv' INTO TABLE t1;Use the
APPENDhint to enable direct load.LOAD DATA /*+ PARALLEL(4) APPEND */ INFILE '/home/admin/test.csv' INTO TABLE t1;
Example 2: Import data from a file in an object storage service system
Use the direct(bool, int) hint to enable direct load. Import data from a file in an object storage service system in direct load mode.
LOAD DATA /*+ direct(true,1024) parallel(16) */ REMOTE_OSS INFILE 'oss://antsys-oceanbasebackup/backup_rd/xiaotao.ht/lineitem2.tbl?host=***.oss-cdn.***&access_id=***&access_key=***' INTO TABLE tbl1 FIELDS TERMINATED BY ',';
Example 3: Import data from a local file on the client
Perform the following steps to import data from a local file to a table in OceanBase Database:
Open a terminal or Command Prompt and enter the following command to start the client:
obclient --local-infile -hxxx.xxx.xxx.xxx -P2881 -usys@oracle001 -p******The return result is as follows:
Welcome to the OceanBase. Commands end with ; or \g. Your OceanBase connection id is 3221548006 Server version: OceanBase 4.2.2.0 (r100000032024010510-75c47d4be18a399e13c5309de1a81da5caf4e7c0) (Built Jan 5 2024 10:17:55) Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. obclient [SYS]>Notice
To use the
LOAD DATA LOCAL INFILEfeature, use OBClient V2.2.4 or later.Execute the
LOAD DATA LOCAL INFILEstatement on the client to load data from a local file.obclient [SYS]> LOAD DATA LOCAL INFILE '/home/admin/test_data/tbl1.csv' INTO TABLE tbl1 FIELDS TERMINATED BY ',';The return result is as follows:
Query OK, 3 rows affected Records: 3 Deleted: 0 Skipped: 0 Warnings: 0
References
- For more information about how to use the
LOAD DATAstatement, see Import data by using the LOAD DATA statement. - For more examples about using the
LOAD DATAstatement for direct load, see Import data through direct load by using the LOAD DATA statement.