min-part-string

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min-part-string [2015/09/23 20:27] (current)
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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)]]