Su, Xiaomeng 76a5b1ee83 dli_sqlreference_20240227

Reviewed-by: Pruthi, Vineet <vineet.pruthi@t-systems.com>
Co-authored-by: Su, Xiaomeng <suxiaomeng1@huawei.com>
Co-committed-by: Su, Xiaomeng <suxiaomeng1@huawei.com>

2024-03-27 22:02:33 +00:00

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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

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