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SQL programmingYou can use the HCL OneDB™ implementation of the SQL language to develop applications for HCL OneDB™ database servers.
Guide to SQL: SyntaxThe HCL OneDB™ Guide to SQL: Syntax describes the syntax of the statements, data types, expressions, operators, and built-in functions of the HCL OneDB™ dialect of the SQL language.
SQL statementsThis chapter describes the syntax and semantics of SQL statements that are recognized by HCL OneDB™.
UPDATE STATISTICS statementUse the UPDATE STATISTICS statement to update system catalog information that the query optimizer uses for operations on objects in the local database. The UPDATE STATISTICS statement is an extension to the ANSI/ISO standard for SQL.
Using the LOW mode optionUse the LOW option of the UPDATE STATISTICS statement to generate and update some of the relevant statistical data regarding table, row, and page-count statistics in the systables system catalog table. If you do not specify any mode, the LOW mode is the default.
Using the DROP DISTRIBUTIONS Option

Using the DROP DISTRIBUTIONS Option

Use the DROP DISTRIBUTIONS option to force the removal of distribution information from the sysdistrib system catalog table.

When you specify the DROP DISTRIBUTIONS option, the database server removes the existing distribution data for the column or columns that you specify. If you do not specify any columns, the database server removes all the distribution data for that table.

You must have the DBA privilege or be owner of the table to use this option.

The following example shows how to remove distributions for the customer_num column in the customer table:

UPDATE STATISTICS LOW 
   FOR TABLE customer (customer_num) DROP DISTRIBUTIONS;

As the example shows, you drop the distribution data at the same time you update the statistical data that the LOW mode option generates.

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