Updated on 2025-03-13 GMT+08:00

General Specifications

  • [Rule] Database valuable features

    Table 1 Recommended database valuable features

    Category

    Feature List

    Description

    Table type

    Partitioned table

    Data partitioning.

    Storage engine

    Row store

    Stores tables by row, which is recommended in the point query and a scenario with many add, delete, and modify operations.

    Transaction

    Transaction block

    Explicitly starts a transaction.

    Single-statement transaction

    Does not explicitly start a transaction. A single statement is a transaction.

    Scale-out

    Online scale-out

    Ensures smooth transition of user services during node scale-out and data redistribution.

    Deployment

    One primary and multiple standby DNs

    One primary DN and multiple standby DNs, ensuring data backup and disaster recovery.

    Security

    Transparent data encryption

    Supports database-level storage encryption. Upper-layer services are unaware of the encryption.

    Data type

    Integer

    TINYINT, SMALLINT, INTEGER, and BIGINT

    Arbitrary-precision

    NUMERIC/DECIMAL

    Floating-point

    REAL/FLOAT4, DOUBLE PRECISION/FLOAT8, and FLOAT

    Boolean

    Boolean

    Fixed-length character

    CHAR(n)

    Variable-length character

    VARCHAR(n), NVARCHAR2(n), and TEXT

    Time

    DATE, TIME, TIMETZ, TIMESTAMP, TIMESTAMPTZ, SMALLDATETIME, INTERVAL, and REALTIME

    Binary

    BYTEA (variable-length binary)

    Bit string

    BIT(n) and VARBIT(n)

    Function

    String function

    String data type processing function.

    Binary string function

    Binary string type processing function.

    Numeric operation function

    Numeric type processing function.

    Time and date processing function

    Time and date type processing function.

    Index

    Primary key or unique index

    Single-column or multi-column primary key or unique index.

    B-tree index

    Index type.

  • [Rule] Recommended best practices for database usage
    Table 2 Recommended best practices for database usage

    No.

    Item

    Recommended Value

    1

    Optimal number of long connections to the database

    For details, see the default configuration of GUC parameter max_connections in the corresponding hardware specifications.

    2

    Maximum data volume on a single physical node

    16 TB (Determine the capacity based on the backup and restoration specifications.)

    3

    Number of active databases

    1

    4

    Total number of database tables and indexes

    10,000 (It is recommended that the number of tables in a single schema be less than or equal to 200.)

    NOTE:

    The value is only a recommended value. You need to plan the value based on the disk capacity and customer services. Theoretically, the maximum value is 232.

    5

    Optimal number of columns in a single table

    < 50

    6

    Optimal number of indexes in a table

    < 5

    7

    Optimal number of composite indexes in a table

    < 3

    8

    Optimal number of columns in a single composite index

    < 5

    9

    Optimal width of a single row

    < 2000

    10

    Optimal capacity of a single column

    < 10 MB

    11

    Optimal SQL statement length

    < 5000

    12

    Percentage of available disk space

    85% (If the disk capacity is greater than 24 TB, 90% is recommended.)