HP NonStop SQL/MP User Manual

Host Variables
HP NonStop SQL/MP Programming Manual for C—429847-008
2-15
Date-Time and INTERVAL Data Types
INTERVAL values are represented as character strings with a separator between the
values of the fields (year-month or day-time). An extra byte is generated at the
beginning of the INTERVAL string for a sign. The default representations for DATE and
INTERVAL values are shown in these examples.
DATE Representation
The column definition and representation in the table for December 22, 1988 is:
birth_date DATE
If the DATEFORMAT clause on the INVOKE directive specifies DEFAULT, a column
with the range of fields YEAR TO DAY is represented as an 11-character string
(10 characters plus a byte for a null character). The C compiler creates this structure:
struct employee_rec {
char name[18];
char birth_date[11];
};
INTERVAL Representation
The column definition and representation in the table for 36 years, 7 months is:
AGE INTERVAL YEAR(2) TO MONTH
The C compiler creates this structure:
struct employee_rec {
char name[21];
char age[7];
};
012
1
9
8
8
1
2
2
2


Year
Separator
Month
Separator
Day
Null
013
+
3
6
0
7

Sign
Year
Separator
Month
Null

HP NonStop SQL/MP Specifications

General

Platform	HP NonStop Servers
Data Model	Relational
SQL Standard	ANSI SQL
Concurrency Control	Multi-Version Concurrency Control (MVCC)
Fault Tolerance	Yes
High Availability	Yes
Category	Database Software
Initial Release	1980s
Operating System	HP NonStop OS
License	Proprietary
Type	Relational Database Management System
Transaction Management	ACID Compliance
Developer	Hewlett Packard Enterprise

Summary

1. Introduction

Developing a C Program

Outlines the process of creating C programs with embedded SQL statements.

Dynamic SQL

Describes how to construct, compile, and run SQL statements at runtime.

2. Host Variables

3. SQL/MP Statements and Directives

4. Data Retrieval and Modification

Single-Row SELECT Statement

Retrieves a single row of data from tables or views into host variables.

Multirow SELECT Statement

Returns multiple rows from tables or views, one row at a time, using cursors.

INSERT Statement

Inserts one or more rows into a table or protection view using host variables.

Using SQL Cursors

Explains how to use named pointers to access sets of rows one at a time.

5. SQL/MP System Procedures

6. Explicit Program Compilation

Explicit Program Compilation

Outlines the general steps for compiling C programs with embedded SQL.

Developing a C Program in the Guardian Environment

Details C program development within the Guardian environment.

Developing a C Program in the OSS Environment

Developing a C Program in a PC Host Environment

7. Program Execution

Required Access Authority

Specifies the access permissions needed to run NonStop SQL program files.

Entering the TACL RUN Command

Running a Program in the OSS Environment

8. Program Invalidation and Automatic SQL Recompilation

Program Invalidation

Explains how SQL program files can become invalid due to changes or errors.

Causes of Program Invalidation

Automatic SQL Recompilation

Describes the run-time recompilation process invoked by the SQL executor.

9. Error and Status Reporting

Returning Error and Warning Information

Using the WHENEVER Directive

10. Dynamic SQL Operations

Uses for Dynamic SQL

Identifies scenarios where dynamic SQL programs are beneficial.

Dynamic SQL Statements

Summarizes dynamic SQL statements usable in a C program.

Dynamic SQL Features

11. Character Processing Rules (CPRL) Procedures

Appendix B: Memory Considerations

Estimating Memory Requirements

Avoiding Memory Stack Overflows

Provides guidelines to prevent stack overflows for SQL statements.