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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™.
SELECT statementUse the SELECT statement to retrieve values from a database or from an SPL or collection variable. A SELECT operation is called a query.
Projection ClauseThe Projection clause (sometimes called the Select clause) specifies a list of database objects or expressions to retrieve, and can set restrictions on qualifying rows. (The select list is sometimes also called the projection list.)
Declaring a Column AliasYou can declare an alias for any column in the select list of the Projection clause. The GROUP BY clause can reference the column by its alias. This temporary name is in scope only while the SELECT statement is executing.

Declaring a Column Alias

You can declare an alias for any column in the select list of the Projection clause. The GROUP BY clause can reference the column by its alias. This temporary name is in scope only while the SELECT statement is executing.

If your alias is an SQL keyword of the SELECT statement, use the AS column_alias keyword to clarify the syntax. For example, to use FROM as a table alias, the AS keyword must immediately precede the alias to avoid a syntax error. The following statement uses AS with from as an alias:

SELECT status AS from FROM stock GROUP BY from;

The following equivalent queries declare pcol as an alias, and use that alias in the GROUP BY clause:

 SELECT pseudo_corinthian AS pcol FROM architecture GROUP BY pcol;
 SELECTt pseudo_corinthian pcol FROM architecture GROUP BY pco1;