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Updated on 2023-10-25 GMT+08:00
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max_pt

This function is used to return the name of the largest level-1 partition that contains data in a partitioned table and read the data of this partition.

Syntax

max_pt(<table_full_name>)

Parameters

Table 1 Parameter

Parameter

Mandatory

Type

Description

table_full_name

Yes

STRING

Specified table name. You must have the read permission on the table.

Return Values

The return value is of the STRING type.

  • The value of the largest level-1 partition is returned.
  • If a partition is added to a table using the ALTER TABLE command, but it does not contain any data, it will not be included in the returned values.

Example Code

For example, table1 is a partitioned table with partitions of 20120801 and 20120802, both of which contain data, and the max_pt value in the following statement will be 20120802. The DLI SQL statement will read data from the partition with pt = 20120802.

An example command is as follows:

select * from tablel where pt = max_pt('dbname.table1');

It is equivalent to the following statement:

select * from table1 where pt = (select max(pt) from dbname.table1);
Parent topic: Other Functions