MySQL

MySQL datasources use the ODBC driver and the MariaDB ODBC connector. The connection string is built internally from the provided fields.

See Supported Data Formats for database source categories and schema column types supported on MySQL connections.

Connection configuration

URI format

mysql://user:password@host:3306/database

The URI is used as a reference identifier. CloudQuant Data Liberator builds the actual ODBC connection string internally from the individual connection fields (server, database, username, password).

Required fields

Field	Type	Description
`connection_type`	string	Must be `"mysql"`
`connection_sub_type`	string	Must be `"database"`
`uri`	string	MySQL connection string
`server`	string	Database host address
`database`	string	Database name
`username`	string	Database user
`password`	string	Database password

Optional fields

Field	Type	Default	Description
`ssl_disabled`	string	`"False"`	Set to `"True"` to disable SSL. Values: `"True"` / `"False"`

Example connection

{
  "name": "mysql-market-data",
  "connection_type": "mysql",
  "connection_sub_type": "database",
  "uri": "mysql://libuser:s3cureP@ss@db.example.com:3306/marketdata",
  "server": "db.example.com",
  "database": "marketdata",
  "username": "libuser",
  "password": "s3cureP@ss",
  "ssl_disabled": "False"
}

Dataset configuration (data_args)

Required fields

Field	Type	Description
`table_options`	list	Tables to query (see below)
`database`	string	Connection reference name
`data_dt_column`	string or list	Column(s) containing the datetime value
`data_dt_format`	bool or string or list	`true` for native datetime auto-detect, or strptime format
`data_dt_timezone`	string	Timezone of the source data
`data_key_column`	string or list	Column(s) used as the symbol/key for query filtering

Optional fields

Field	Type	Default	Description
`batch_size`	int	`10000`	Number of rows per query batch
`data_dt_nudge`	int	`0`	Microsecond offset applied to timestamps

table_options entry

Each entry in table_options describes a table to query:

Field	Type	Description
`db`	string	Database name
`table_like`	string	Table name or pattern
`token`	string	Table identifier token
`zone`	string	Timezone, default `"America/New_York"`
`dt_mode`	string	(Optional) Datetime mode
`dt_regex`	string	(Optional) Regex for partitioned tables
`dt_format`	string	(Optional) Datetime format for partitioned tables
`nudge_micros`	int	(Optional) Microsecond nudge

Complete example

Connection

{
  "name": "mysql-trades",
  "connection_type": "mysql",
  "connection_sub_type": "database",
  "uri": "mysql://libuser:s3cureP@ss@db.example.com:3306/trades_db",
  "server": "db.example.com",
  "database": "trades_db",
  "username": "libuser",
  "password": "s3cureP@ss",
  "ssl_disabled": "False"
}

Dataset

{
  "name": "us-equity-trades",
  "connection": "mysql-trades",
  "data_args": {
    "table_options": [
      {
        "db": "trades_db",
        "table_like": "daily_trades",
        "token": "daily_trades",
        "zone": "America/New_York"
      }
    ],
    "database": "mysql-trades",
    "batch_size": 10000,
    "data_dt_column": "trade_time",
    "data_dt_format": true,
    "data_dt_timezone": "America/New_York",
    "data_dt_nudge": 0,
    "data_key_column": "symbol"
  },
  "schema": [
    { "name": "symbol", "type": "string", "group": "key", "description": "Ticker symbol" },
    { "name": "trade_time", "type": "string", "group": "time", "description": "Trade timestamp" },
    { "name": "price", "type": "double", "group": "value", "description": "Trade price" },
    { "name": "volume", "type": "int64", "group": "value", "description": "Trade volume" },
    { "name": "exchange", "type": "string", "group": "value", "description": "Exchange code" }
  ]
}

Set data_dt_format to true when using native MySQL DATETIME or TIMESTAMP columns. CloudQuant Data Liberator will auto-detect the datetime type and convert directly without string parsing.

SSL configuration

By default, SSL is enabled. To disable SSL (e.g., for local development):

{
  "ssl_disabled": "True"
}

Disabling SSL in production is not recommended. Always use SSL when connecting over untrusted networks. The MariaDB ODBC driver supports TLS 1.2+ by default.

Driver and dependencies

Component	Details
Driver	`ODBC driver` with MariaDB ODBC 3.2+
Protocol	ODBC
Arrow conversion	High-performance ODBC driver
ODBC required	Yes (MariaDB ODBC connector)
Default port	3306

The MariaDB ODBC 3.2+ driver must be installed on the CloudQuant Data Liberator host. This driver is compatible with both MySQL and MariaDB servers. Verify installation with odbcinst -q -d.

Troubleshooting

ODBC driver not found

If you see errors about missing ODBC drivers, verify the MariaDB ODBC driver is installed and registered:

# List installed ODBC drivers
odbcinst -q -d

# Expected output should include:
# [MariaDB ODBC 3.2 Driver]

Install the driver if missing:

apt-get install libmariadb3 odbc-mariadb

yum install MariaDB-connector-odbc

Connection refused

Verify the MySQL server is accepting connections on the specified host and port. Check that the bind-address in the MySQL configuration allows remote connections.

mysql -h db.example.com -P 3306 -u libuser -p marketdata

Authentication failed

Ensure the user has been granted access from the CloudQuant Data Liberator host’s IP address:

GRANT SELECT ON trades_db.* TO 'libuser'@'liberator-host' IDENTIFIED BY 's3cureP@ss';
FLUSH PRIVILEGES;

SSL handshake errors

If SSL connections fail, check that the MySQL server’s SSL certificate is valid and trusted. Set ssl_disabled to "True" temporarily to confirm the issue is SSL-related.

Slow queries

Increase batch_size for large result sets (up to 100000).
Ensure the datetime and key columns are indexed in MySQL.
For partitioned tables, ensure dt_regex is correctly scoping queries to relevant partitions.

​MySQL

​Connection configuration

​URI format

​Required fields

​Optional fields

​Example connection

​Dataset configuration (data_args)

​Required fields

​Optional fields

​table_options entry

​Complete example

​Connection

​Dataset

​SSL configuration

​Driver and dependencies

​Troubleshooting

​ODBC driver not found

​Connection refused

​Authentication failed

​SSL handshake errors

​Slow queries

MySQL

Connection configuration

URI format

Required fields

Optional fields

Example connection

Dataset configuration (data_args)

Required fields

Optional fields

table_options entry

Complete example

Connection

Dataset

SSL configuration

Driver and dependencies

Troubleshooting

ODBC driver not found

Connection refused

Authentication failed

SSL handshake errors

Slow queries