TiCDC CSV Protocol

When using a cloud storage service as the downstream sink, you can send DML events to the cloud storage service in CSV format.

Use CSV

The following is an example of the configuration when using the CSV protocol:

cdc cli changefeed create --server=http://127.0.0.1:8300 --changefeed-id="csv-test" --sink-uri="s3://bucket/prefix" --config changefeed.toml

The configuration in the changefeed.toml file is as follows:

[sink]
protocol = "csv"
terminator = "\n"

[sink.csv]
delimiter = ','
quote = '"'
null = '\N'
include-commit-ts = true

Transactional constraints

• In a single CSV file, the commit-ts of a row is equal to or smaller than that of the subsequent row.
• The same transactions of a single table are stored in the same CSV file.
• Multiple tables of the same transaction can be stored in different CSV files.

Data storage path structure

For more information about the storage path structure of the data, see Storage path structure.

Definition of the data format

In the CSV file, each column is defined as follows:

• Column 1: The operation-type indicator, including I, U, and D. I means INSERT, U means UPDATE, and D means DELETE.
• Column 2: Table name.
• Column 3: Schema name.
• Column 4: The commit-ts of the source transaction. This column is optional.
• Column 5 to the last column: One or more columns that represent data to be changed.

Assume that table hr.employee is defined as follows:

CREATE TABLE `employee` (
  `Id` int NOT NULL,
  `LastName` varchar(20) DEFAULT NULL,
  `FirstName` varchar(30) DEFAULT NULL,
  `HireDate` date DEFAULT NULL,
  `OfficeLocation` varchar(20) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

The DML events of this table are stored in the CSV format as follows:

"I","employee","hr",433305438660591626,101,"Smith","Bob","2014-06-04","New York"
"U","employee","hr",433305438660591627,101,"Smith","Bob","2015-10-08","Los Angeles"
"D","employee","hr",433305438660591629,101,"Smith","Bob","2017-03-13","Dallas"
"I","employee","hr",433305438660591630,102,"Alex","Alice","2017-03-14","Shanghai"
"U","employee","hr",433305438660591630,102,"Alex","Alice","2018-06-15","Beijing"

Data type mapping