ESQL reference

SQL is the industry standard language for accessing and updating database data and ESQL is a language derived from SQL Version 3, particularly suited to manipulating both database and message data.

This section covers the following topics:

Syntax diagrams: This describes the formats that are available for viewing ESQL syntax diagrams.
ESQL data types in message flows: This describes the valid data types for ESQL.
ESQL field reference overview: This topic describes the syntax of field references.
Special characters, case sensitivity, and comments in ESQL: This describes the special characters you use when writing ESQL statements.
ESQL operators: This describes the operators that are available.
ESQL reserved keywords: This lists the reserved keywords which you cannot use for variable names.
ESQL non-reserved keywords: This lists the keywords that are not reserved, as well as those reserved for future releases, which you can use if you choose.
ESQL functions: This topic lists the functions available in ESQL, and what they do.
ESQL constants: This topic lists the constants available in ESQL, and what they do.
ESQL statements: This topic lists the different statement types available in ESQL, and what they do.
Calling ESQL functions: This topic describes all the ESQL functions in detail.
ESQL variables: This topic describes the types of ESQL variable and their lifetimes.
Integration node properties that are accessible from ESQL, the Mapping node, and Java: This topic lists the integration node attributes that can be accessed from ESQL code.

An XML format message that is used in many of the ESQL examples in these topics is shown in Example message.

For information about how you can use ESQL statements and functions to configure Compute, Database, and Filter nodes, see Writing ESQL.