Extending Informix Dynamic Server 2000 Running a User-Defined Routine

In This Chapter

Invoking a User-Defined Routine

Invoking a UDR in an SQL Statement

Invoking a UDR with an EXECUTE Statement

Invoking a User-Defined Function in an Expression

Invoking a Function That Is Bound to an Operator

Invoking a UDR in an SPL Routine

Executing a User-Defined Routine

Parsing the SQL Statement

Optimizing the SQL Statement

Executing an External Routine

Loading a Shared-Object File into Memory

Creating the Routine Sequence

Managing Routine Execution

Executing an SPL Routine

Understanding Routine Resolution

The Routine Signature

Using ANSI and Non-ANSI Routine Signatures

Using the Routine Signature to Perform DBA Tasks

Overloading Routines

Creating Overloaded Routines

Assigning a Specific Routine Name

Specifying Overloaded Routines During Invocation

Overloading Built-In SQL Functions

The Routine-Resolution Process

The Routine Signature

Candidate List of Routines

Precedence List of Data Types

Precedence List for Built-In Data Types

Routine Resolution with User-Defined Data Types

Routine Resolution in a Type Hierarchy

Routine Resolution with Distinct Data Types

Routine Resolution with Built-In Data Types as Source

Routine Resolution with Collection Data Types

Null Arguments in Overloaded Routines