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SQL programming
You can use the HCL Informix® implementation of the SQL language to develop applications for Informix database servers.
Guide to SQL: Syntax
The Informix® Guide to SQL: Syntax describes the syntax of the statements, data types, expressions, operators, and built-in functions of the Informix dialect of the SQL language.
SPL statements
These topics describe Stored Procedure Language (SPL) statements, which you use to write SPL routines. You can store these routines in the database as user-defined routines (UDRs).
ON EXCEPTION
Using the IN Clause to Trap Specific Exceptions

SQL programming
You can use the HCL Informix® implementation of the SQL language to develop applications for Informix database servers.
- Guide to SQL: Syntax
  The Informix® Guide to SQL: Syntax describes the syntax of the statements, data types, expressions, operators, and built-in functions of the Informix dialect of the SQL language.
  - Overview of SQL syntax
    These topics provide an overview about how to use the SQL statements, SPL statements, and syntax segments.
  - SQL statements
    This chapter describes the syntax and semantics of SQL statements that are recognized by Informix®.
  - SPL statements
    These topics describe Stored Procedure Language (SPL) statements, which you use to write SPL routines. You can store these routines in the database as user-defined routines (UDRs).
    - << Label >> statement
      Use the <<label>> statement of SPL to declare a statement label or a loop label.
    - CALL
    - CASE
      Use the CASE statement when program execution needs to take exactly one among multiple branches, depending on the value of an SPL variable or of a simple expression. The CASE statement is a logical alternative to the IF statement.
    - CONTINUE
    - DEFINE
    - EXIT
    - FOR
    - FOREACH
      Use the FOREACH statement to declare a direct cursor that can select and manipulate more than one row from a the result set of a query, or more than one element from a collection.
    - GOTO
    - IF
    - LET
    - LOOP
    - ON EXCEPTION
      - Placement of the ON EXCEPTION statement
        The ON EXCEPTION statement is a declarative statement, not an executable statement. For this reason, ON EXCEPTION must follow immediately after any DEFINE statements, and must precede any executable statement within the same SPL statement block.
      - Using the IN Clause to Trap Specific Exceptions
      - Receiving Error Information in the SET Clause
      - Forcing Continuation of the Routine
    - RAISE EXCEPTION
    - RETURN
    - SYSTEM
    - TRACE
    - WHILE
      Use the WHILE statement to establish a loop with variable end conditions.
  - Data types and expressions
    These topics describe the data types and expressions that Informix®supports.
  - Other syntax segments
    These topics describe syntax segments, which are language elements, such as database object names or optimizer directives, that appear as a subdiagram reference in the syntax diagrams of some SQL or SPL statements.
  - Built-In Routines
  - Appendixes
- Guide to SQL: Reference
  The Informix® Guide to SQL: Reference contains the reference information for the system catalog tables, data types, and environment variables of the HCL Informix dialect of the SQL language, as implemented in HCL Informix. These topics also include information about the stores_demo, sales_demo, and superstore_demo databases that are included with HCL Informix.
- Guide to SQL: Tutorial
  The Informix® Guide to SQL: Tutorial shows how to use basic and advanced structured query language (SQL) to access and manipulate the data in your databases. It discusses the data manipulation language (DML) statements as well as triggers and stored procedure language (SPL) routines, which DML statements often use.

Using the IN Clause to Trap Specific Exceptions

An error is trapped if the SQL error code or the ISAM error code matches an exception code in the list of error numbers. The search through the list of errors begins from the left and stops with the first match. You can use a combination of an ON EXCEPTION statement without an IN clause and one or more ON EXCEPTION statements with an IN clause. When an error occurs, the database server searches for the last declaration of the ON EXCEPTION statement that traps the particular error code.

CREATE PROCEDURE ex_test()
   DEFINE error_num INT;
   ...
   ON EXCEPTION SET error_num
   -- action C
   END EXCEPTION
   ON EXCEPTION IN (-300)
   -- action B
   END EXCEPTION
   ON EXCEPTION IN (-210, -211, -212) SET error_num
   -- action A
   END EXCEPTION

A summary of the sequence of statements in the previous example would be:

Test for an error.
If error -210, -211, or -212 occurs, take action A.
If error -300 occurs, take action B.
If any other error occurs, take action C.