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+ | ====== MIN_PART_STRING Function - PL/HQL ====== | ||
+ | MIN_PART_STRING function finds the minimum value (first in alphabetical order) for the specified partition column of type STRING (VARCHAR/CHAR). | ||
+ | |||
+ | **Syntax**: | ||
+ | |||
+ | <code language="sql"> | ||
+ | MIN_PART_STRING([db_name.]table_name [, column_name [, part_col=filter, ...]]); | ||
+ | </code> | ||
+ | |||
+ | **Parameters:** | ||
+ | |||
+ | | **Parameter** | **Type** | **Value** | **Description** | | ||
+ | | [dbname.]table_name | VARCHAR | Identifier, variable or expression | Table name | | ||
+ | | column_name | VARCHAR | Identifier, variable or expression | Partition column name | | ||
+ | | part_col=filter | | | Partition filter | | ||
+ | |||
+ | **Notes**: | ||
+ | |||
+ | * If column name is not specified, the first partition column is used | ||
+ | * Partition filter applied before finding the minimum value | ||
+ | |||
+ | **Return Value:** | ||
+ | |||
+ | * The minimum string for the specified partition | ||
+ | * NULL if the table or partition do not exist, or the table is empty | ||
+ | |||
+ | **Return Type:** | ||
+ | |||
+ | STRING (VARCHAR/CHAR). | ||
+ | |||
+ | **Example 1:** | ||
+ | |||
+ | Table //db.orders// is partitioned by //country// and has the following partitions: | ||
+ | |||
+ | | country=US | | ||
+ | | country=UK | | ||
+ | | country=DE | | ||
+ | |||
+ | Find the minimum value of the partition: | ||
+ | |||
+ | <code language="sql"> | ||
+ | MIN_PART_STRING(db.orders); | ||
+ | </code> | ||
+ | |||
+ | Result: DE | ||
+ | |||
+ | **Example 2:** | ||
+ | |||
+ | Table //db.sales// is partitioned by //country// and //local_date// and has the following partitions: | ||
+ | |||
+ | | country=US/local_date=2014-12-02 | | ||
+ | | country=DE/local_date=2014-12-04 | | ||
+ | | country=UK/local_date=2014-12-04 | | ||
+ | |||
+ | Find the minimum value for //country// partition column for local_date '2014-12-04': | ||
+ | |||
+ | <code language="sql"> | ||
+ | MIN_PARTITION_STRING(db.sales, country, local_date='2014-12-04'); | ||
+ | </code> | ||
+ | |||
+ | Result: DE | ||
+ | |||
+ | **Compatibility**: PL/HQL extension. | ||
+ | |||
+ | **Version:** PL/HQL 0.01 | ||
+ | |||
+ | See also: | ||
+ | |||
+ | * [[max-part-string|MAX_PART_STRING(table, colname, partition_spec)]] | ||
+ | * [[max-part-int|MAX_PART_INT(table, colname, partition_spec)]] | ||
+ | * [[min-part-int|MIN_PART_INT(table, colname, partition_spec)]] | ||
+ | * [[max-part-date|MAX_PART_DATE(table, colname, partition_spec)]] | ||
+ | * [[min-part-date|MIN_PART_DATE(table, colname, partition_spec)]] |