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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™.
PREPARE statementUse the PREPARE statement to parse, validate, and generate an execution plan for one or more SQL statements at runtime.
Releasing a Statement Identifier

Releasing a Statement Identifier

A statement identifier can represent only one SQL statement or (in ESQL/C) one semicolon-separated list of SQL statements at a time. A new PREPARE statement can specify an existing statement identifier if you want to bind the identifier to a different SQL statement text.

The PREPARE statement supports dynamic statement-identifier names, which allow you to prepare a statement identifier as an identifier or (in ESQL/C) as a host variable of a data type that can contain a character string. The first example that follows shows a statement identifier that was specified as a host variable. The second specifies a statement identifier as a character string.

stcopy ("query2", stmtid);
EXEC SQL prepare :stmtid from 'select * from customer';

EXEC SQL prepare query2 from 'select * from customer';

The variable must be a character data type. In C, it must be declared as char.

In an SPL routine, statement identifiers that the PREPARE statement declares are automatically defined in the local scope. Do not attempt to declare a statement identifier as having local or global scope. A statement identifier defined in one SPL routine is not visible to any other SPL routine that the same session calls. SPL statement identifiers share the same namespace as SPL variables and cursor names.