To ensure the stability and security of clusters, AnalyticDB for MySQL is subject to the following limits.

Object Naming convention Limit
Database name A database name can be up to 64 characters in length and can contain letters, digits, and underscores (_). It must start with a lowercase letter and cannot contain consecutive underscores (_). Do not use analyticdb as the database name. The name analyticdb is reserved for a built-in database.
Table name A column name must be 1 to 127 characters in length, and can contain letters, digits, and underscores (_). It must start with a letter or underscore (_).
  • A table name cannot contain single quotation marks ('), double quotation marks (''), exclamation points (!), or spaces.
  • A table name cannot be SQL reserved keywords.
Column name A column name must be 1 to 127 characters in length, and can contain letters, digits, and underscores (_). It must start with a letter or underscore (_).
  • A column name cannot contain single quotation marks ('), double quotation marks (''), exclamation points (!), or spaces.
  • A column name cannot be SQL reserved keywords.
Account name An account name must be 2 to 16 characters in length, and can contain lowercase letters, digits, and underscores (_). It must start with a lowercase letter and end with a lowercase letter or digit. None
Password A password must be 8 to 32 characters in length and must contain at least three of the following character types: uppercase letters, lowercase letters, digits, and special characters. Special characters include ! @ # $ % ^ & * () _ + - = None
Comment in a table None A column comment can be up to 1,024 characters in length.
Comment in a column None A column comment can be up to 1,024 characters in length.
Index name None An index name can be up to 64 characters in length.
Default value of a column None The default value of a column can be up to 127 characters in length.

Limits on purchase and configurations

Limit Description Remarks
The maximum number of clusters that you can purchase in each Alibaba cloud account 64 None
The maximum number of node groups that you can purchase for each cluster, excluding C4 node groups 128 C4 node groups are excluded.
The maximum number of C4 node groups that you can purchase for each cluster 4 None
The disk space that you can purchase for each C4 node group 100GB~200GB None
The minimum number of node groups that you can purchase for each cluster 2 None
The maximum number of databases that you can create in each cluster 256 None
The total number of scale-in, scale-out, upgrade, and downgrade operations on each cluster per day 12 None
The threshold of the disk space usage for node groups 80% If the disk space usage of a cluster exceeds this threshold, the cluster is locked and data cannot be written to the cluster.
The maximum number of standard accounts that you can create for each cluster 256 None
The maximum number of connections that you can establish with each cluster 5000 None
The maximum number of tables that you can create in each cluster
  • Reserved mode

    Cluster Edition: 1 to 20 node groups and 5,000 tables. You can increase the number of tables by expanding the number of nodes.

  • Elastic mode

    Computing resources contain less than 1,440 cores and 5,000 tables. You can increase the number of tables by scaling out the number of nodes.

None
The maximum number of columns in each table 4096 None
The maximum number of partitions in each table 102400 None
The maximum number of IP addresses that you can add to whitelists in each cluster 25000 You can create up to 50 whitelists within each cluster and add up to 1,000 IP addresses to each whitelist.
The maximum number of items that you can specify in the WHERE clause 256 None
The maximum number of conditions that you can specify by using the IN operator 2000 None
The maximum length of data that you can write in each row 16MB None
The maximum length of each field 16MB None
The valid values of the M and D parameters in the DECIMAL(M,D) data type M is the maximum precision, and its value range is 1 to 1,000. D is the decimal scale. The value of D must be less than or equal to that of M. None

Limits on operations

Operation Timeout period (unit: ms) Timeout description
Create a cluster 600000 None
Delete a cluster 300000 None
Scale out a cluster 600000 None
Create a database 10000 None
Delete a database 10000 None
Create a table or view 10000 None
Delete a table or view 10000 None
Insert a column 10000 None
Delete a column 60000 None
Update a column 60000 None
TRUNCATE TABLE 60000 None
Query data 1800000 When a query times out, the system automatically ends the query. You can modify the maximum execution time of a query by modifying the following configuration:
  • Parameter: queryTimeout
  • Hint: query_timeout
Write data 300000 None
INSERT SELECT FROM 24*3600000 When a task times out and ends, you can modify the maximum execution time of the INSERT SELECT FROM statement by modifying the following configuration:
  • Parameter: insertSelectTimeout
  • Hint: insert_select_timeout
INSERT OVERWRITE 24*3600000 When a task times out and ends, you can modify the maximum execution time of the INSERT OVERWRITE statement by modifying the following configuration:
  • Parameter: insertSelectTimeout
  • Hint: insert_select_timeout