How to create a Logtail configuration to collect MySQL query results - Simple Log Service

This topic describes how to create a Logtail configuration in the Simple Log Service console to collect MySQL query results.

Prerequisites

Logtail V0.16.0 or later is installed on a Linux server, or Logtail V1.0.0.8 or later is installed on a Windows server. For more information, see Install Logtail on a Linux server or Install Logtail on a Windows server.
Important
Make sure that the server on which Logtail is installed can connect to the MySQL database from which you want to collect MySQL query results.
The IP address of the server on which Logtail is installed is added to a whitelist of the MySQL database from which you want to collect MySQL query results.
For more information about how to configure a whitelist, see Configure an IP address whitelist for an ApsaraDB RDS for MySQL instance.

Principle

Logtail executes the SELECT statement that is specified in a Logtail configuration on a regular basis, and then uploads the query results to Simple Log Service.

After Logtail obtains query results, Logtail saves the value of the CheckPoint field in the results to the Logtail server. The next time Logtail executes the SELECT statement, Logtail adds the value of the CheckPoint field to the SELECT statement. This way, Logtail can collect incremental data.

Important

If you use checkpoints during data collection, you must sort the values of the CheckPoint field in the SELECT statement. Otherwise, data duplication or other issues may occur.

Features

You can collect query results from MySQL databases.
You can configure paged query settings.
You can specify time zones.
You can specify timeout periods.
You can save the values of the CheckPoint field.
SSL is supported.
You can specify the maximum number of logs that can be collected at a time.

Scenarios

Collect incremental data based on marks such as an auto-increment ID or a point in time.
Synchronize data based on filter conditions.

Procedure

Log on to the Simple Log Service console.
In the Quick Data Import section, click Import Data. In the Import Data dialog box, click MySQL Query Result - Plug-in.
Select the project and Logstore. Then, click Next.
In the Machine Group Configurations step, configure a machine group.
1. Configure the Scenario and Installation Environment parameters based on your business requirements.
  Important
  You must configure the Scenario and Installation Environment parameters regardless of whether a machine group is available. The parameter settings affect subsequent configurations.
2. Make sure that a machine group is displayed in the Applied Server Groups section and click Next.
  Machine group available
  Select a machine group from the Source Machine Group section.
  No machine group available
  Click Create Machine Group. In the Create Machine Group panel, configure the parameters. You can set the Machine Group Identifier parameter to IP Address or Custom Identifier. For more information, see Create a custom identifier-based machine group or Create an IP address-based machine group.
  Important
  If you apply a machine group immediately after you create the machine group, the heartbeat status of the machine group may be FAIL. This issue occurs because the machine group is not connected to Simple Log Service. To resolve this issue, you can click Retry. If the issue persists, see What do I do if no heartbeat connections are detected on Logtail?
In the Configure Data Source step, configure the Configuration Name and Plug-in Configuration parameters. Then, click Next.
You can specify a data source by using one of the following methods: form configuration and editor configuration in JSON. For more information, see Details of the Logtail configuration.
Create indexes and preview data. Then, click Next. By default, full-text indexing is enabled in Simple Log Service. You can also manually create field indexes for the collected logs or click Automatic Index Generation. Then, Simple Log Service generates field indexes. For more information, see Create indexes.
Important
If you want to query all fields in logs, we recommend that you use full-text indexes. If you want to query only specific fields, we recommend that you use field indexes. This helps reduce index traffic. If you want to analyze fields, you must create field indexes. You must include a SELECT statement in your query statement for analysis.
Click Log Query. You are redirected to the query and analysis page of your Logstore.
You must wait approximately 1 minute for the indexes to take effect. Then, you can view the collected logs on the Raw Logs tab. For more information, see Query and analyze logs.

Details of the Logtail configuration

You can specify a data source by using one of the following methods: form configuration and editor configuration in JSON.

Form configuration

In the Configure Data Source step, configure the parameters. The following table describes the parameters.

Parameter	Description
Configuration Name	The name of the Logtail configuration.
MySQL Address	The address of the MySQL database. Example: `rm-****.mysql.rds.aliyuncs.com`
Database Username	The username of the account that is used to log on to the MySQL database.
Database Password	The password of the account that is used to log on to the MySQL database. If you have high requirements for data security, we recommend that you set the username and password to `xxx`. After your configuration is synchronized to the Logtail server, find the two parameters in the /usr/local/ilogtail/user_log_config.json file and change the values based on your business requirements. For more information, see Modify the Logtail configuration on the Logtail server. Important If you modify this parameter in the Simple Log Service console, the parameter setting in the Logtail configuration on the Logtail server is overwritten after the modification is synchronized to the server.
Database Name	The name of the MySQL database.
Database Connection Timeout Period	The timeout period for connections to the MySQL database. Unit: milliseconds.
Query Timeout Period	The timeout period for reads from the MySQL database. Unit: milliseconds.
SELECT Statement	The SELECT statement. If you select Use CheckPoint, you must include the column that is specified for the CheckPoint Column Name parameter in a WHERE clause of the SELECT statement that you specify for the SELECT Statement parameter. You can use question marks (?) to indicate replacement characters. If you use a question mark (?) in the SELECT statement, you must also configure the CheckPoint Column Name parameter. Important For example, set the CheckPoint Column Name parameter to `id`, the Initial Value of CheckPoint Column parameter to 0, and the SELECT Statement parameter to `SELECT * FROM xxx WHERE ID > ?`. Each time Logtail executes the SELECT statement, the system saves the ID of the last data record as the checkpoint. The next time Logtail executes the SELECT statement, the question mark (?) that is specified in the SELECT statement is replaced with the ID that corresponds to the saved checkpoint.
Use LIMIT Clause to Perform Paged Queries	Specifies whether to use a LIMIT clause to paginate query results. We recommend that you select Use LIMIT Clause to Perform Paged Queries. If you select Use LIMIT Clause to Perform Paged Queries, a LIMIT clause is automatically added to the SELECT statement that you specify for the SELECT Statement parameter when Logtail executes the SQL statement.
Page Size	The maximum number of logs that can be returned on each page. If you select Use LIMIT Clause to Perform Paged Queries, you must configure this parameter.
Maximum Records per Synchronization	The maximum number of logs that can be synchronized at a time. Default value: 0, which indicates that the number is unlimited.
Use CheckPoint	Specifies whether to use checkpoints during data collection. If you select Use CheckPoint, checkpoints are used during data collection. A checkpoint can be used as the start point of the next data collection. This way, incremental data is collected.
CheckPoint Column Name	The name of the column that stores checkpoints. If you select Use CheckPoint, you must configure this parameter. Warning Values in the checkpoint column must be incremental. Otherwise, some data may not be collected. The maximum value in the results of a query operation is used as the input for the next query operation.
Data Type of CheckPoint Column	The type of the checkpoint column. Valid values: int and time. If you set this parameter to int, the values in the checkpoint column are of the int64 type. If you set this parameter to time, the values in the checkpoint column can be of the date, datetime, or time type that is supported by MySQL. If you select Use CheckPoint, you must configure this parameter.
Initial Value of CheckPoint Column	The initial value of the checkpoint column. If you select Use CheckPoint, you must configure this parameter.
Save CheckPoint per Pagination	If you select Save CheckPoint per Pagination, checkpoints are saved each time query results are paginated. If you do not select Save CheckPoint per Pagination, checkpoints are saved each time query results are synchronized.
Synchronized At	The synchronization interval. Unit: milliseconds.

Editor configuration in JSON

In the Plug-in Configuration field, enter information about your Logtail configuration.

inputs is required and is used to configure the data source settings for the Logtail configuration.
Important
You can specify only one type of data source in inputs.
processors is optional and is used to configure the data processing settings for the Logtail configuration to parse data. You can specify one or more processing methods.
If your logs cannot be parsed based only on the setting of inputs, you can configure processors in the Plug-in Configuration field to add plug-ins for data processing. For example, you can extract fields, extract log time, mask data, and filter logs. For more information, see Use Logtail plug-ins to process data.

{
  "inputs": [
    {
      "type": "service_mysql",
      "detail": {
        "Address": "************.mysql.rds.aliyuncs.com",
        "User": "****",
        "Password": "*******",
        "DataBase": "****",
        "Limit": true,
        "PageSize": 100,
        "StateMent": "select * from db.VersionOs where time > ?",
        "CheckPoint": true,
        "CheckPointColumn": "time",
        "CheckPointStart": "2018-01-01 00:00:00",
        "CheckPointSavePerPage": true,
        "CheckPointColumnType": "time",
        "IntervalMs": 60000
      }
    }
  ]
}

Parameter	Type	Required	Description
type	string	Yes	The type of the data source. Set the value to service_mysql.
Address	string	No	The address of the MySQL database. Example: `rm-****.mysql.rds.aliyuncs.com` Default value: 127.0.0.1:3306.
User	string	No	The username of the account that is used to log on to the MySQL database. Default value: root.
Password	string	No	The password of the account that is used to log on to the MySQL database. By default, this parameter is left empty. If you have high requirements for data security, we recommend that you set the username and password to `xxx`. After your configuration is synchronized to the Logtail server, find the two parameters in the /usr/local/ilogtail/user_log_config.json file and change the values based on your business requirements. For more information, see Modify the Logtail configuration on the Logtail server. Important If you modify this parameter in the Simple Log Service console, the parameter setting in the Logtail configuration on the Logtail server is overwritten after the modification is synchronized to the server.
DataBase	string	No	The name of the MySQL database.
DialTimeOutMs	int	No	The timeout period for connections to the MySQL database. Unit: milliseconds. Default value: 5000.
ReadTimeOutMs	int	No	The timeout period for reads from the MySQL database. Unit: milliseconds. Default value: 5000.
StateMent	string	No	The SELECT statement. If you set the CheckPoint parameter to true, you must include the column that is specified for the CheckPointColumn parameter in a WHERE clause of the SELECT statement that you specify for the StateMent parameter. You can use question marks (?) to indicate replacement characters. If you use a question mark (?) in the SELECT statement, you must also configure the CheckPointColumn parameter. For example, set the CheckPointColumn parameter to id, the CheckPointStart parameter to 0, and the StateMent parameter to `SELECT * from ... where id > ?`. Each time Logtail executes the SELECT statement, the system saves the ID of the last data record as the checkpoint. The next time Logtail executes the SELECT statement, the question mark (?) that is specified in the SELECT statement is replaced with the ID that corresponds to the saved checkpoint.
Limit	boolean	No	Specifies whether to use a LIMIT clause to paginate query results. Valid values: true false (default) We recommend that you set the Limit parameter to true. If you set the Limit parameter to true, a LIMIT clause is automatically added to the SELECT statement that you specify for the StateMent parameter when Logtail executes the SQL statement.
PageSize	int	No	The maximum number of logs that can be returned on each page. If you set the Limit parameter to true, you must configure this parameter.
MaxSyncSize	int	No	The maximum number of logs that can be synchronized at a time. Default value: 0, which indicates that the number is unlimited.
CheckPoint	boolean	No	Specifies whether to use checkpoints during data collection. Valid values: true false (default) A checkpoint can be used as the start point of the next data collection. This way, incremental data is collected.
CheckPointColumn	string	No	The name of the column that stores checkpoints. If you set the CheckPoint parameter to true, you must configure this parameter. Warning Values in the checkpoint column must be incremental. Otherwise, some data may not be collected. The maximum value in the results of a query operation is used as the input for the next query operation.
CheckPointColumnType	string	No	The type of the checkpoint column. Valid values: int and time. If you set this parameter to int, the values in the checkpoint column are of the int64 type. If you set this parameter to time, the values in the checkpoint column can be of the date, datetime, or time type that is supported by MySQL. If you set the CheckPoint parameter to true, you must configure this parameter.
CheckPointStart	string	No	The initial value of the checkpoint column. If you set the CheckPoint parameter to true, you must configure this parameter.
CheckPointSavePerPage	boolean	No	Specifies whether to save checkpoints each time query results are paginated. Valid values: true (default): saves checkpoints each time query results are paginated. false: saves checkpoints each time query results are synchronized.
IntervalMs	int	Yes	The synchronization interval. Unit: milliseconds. Default value: 60000.

Modify the Logtail configuration on the Logtail server

If you did not enter real information for parameters such as Address, User, and Password in the Plug-in Configuration field when you created the Logtail configuration, you can modify the parameters after the Logtail configuration is delivered to the Logtail server.

Linux

Log on to the Logtail server.
Find the service_mysql keyword in the /usr/local/ilogtail/user_log_config.json file and modify parameters such as Address, User, and Password.

Run the following command to restart Logtail:

sudo /etc/init.d/ilogtaild stop; sudo /etc/init.d/ilogtaild start

Windows

Log on to the Logtail server.
Find the service_mysql keyword in the C:\Program Files\Alibaba\Logtail\user_log_config.json file, and modify parameters such as Address, User, and Password.
The file locations differ between Windows 64-bit operating systems and Windows 32-bit operating systems. For more information, see File path.
Run the following command to restart Logtail.
1. Choose Start Menu > Control Panel > Administrative Tools > Services.
2. In the Services dialog box, select the service that you want to manage.
  - For Logtail V0.x.x.x, select LogtailWorker.
  - For Logtail V1.0.0.0 or later, select LogtailDaemon.
3. Right-click the service and select Start, Stop, or Restart.

Troubleshooting

If no data is displayed on the preview page or query page after logs are collected by using Logtail, you can troubleshoot the errors based on the instructions that are provided in What do I do if errors occur when I use Logtail to collect logs?

Sample database table and sample log

This section provides a sample database table and a sample log that is collected by Logtail.

Sample database table

CREATE TABLE `VersionOs` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT 'id',
  `time` datetime NOT NULL,
  `version` varchar(10) NOT NULL DEFAULT '',
  `os` varchar(10) NOT NULL,
  `count` int(11) unsigned NOT NULL,
  PRIMARY KEY (`id`),
  KEY `timeindex` (`time`)
)

Sample log

"count":  "4"  
"id:  "721097"  
"os:  "Windows"  
"time:  "2022-08-25 13:00:00"  
"version":  "1.3.0"