About This Document
Organization of This Guide
Database Access Methods
Transactional Programming with the MicroKernel Engine
Relational Programming
Appendixes
Overview of Zen Access Methods
Developer Quick Start
Choosing An Access Method
Database Connection Quick Reference
ADO.NET Connections
Sample ADO.NET DB Connection Code
JDBC Connections
Sample JDBC Connection Code
Java Class Library
Sample JCL Connection String
DSN-Less Connections
Example
ODBC Information
Other SQL Access Methods
JDBC
PDAC
Additional Resources for Application Developers
Conceptual Information
Reference Information
Online Developer Resources
Sample Code
Developing Applications for the MicroKernel Engine
MicroKernel Engine Environment
Documentation
Configuration Issues for MicroKernel Engine
MicroKernel Engine Fundamentals
Overview of the MicroKernel Engine
MicroKernel Engine Environment
Configuration Notes
Pages
Page Types
Page Size
Page Size Criteria
Large vs. Small Page Size
Factors To Consider When Determining Page Size
File Types
Standard Data Files
Data-Only Files
Key-Only Files
Large Files
Long File Names
Data Types
Key Attributes
Key Attributes Description
Segmentation
Duplicatability
Modifiability
Sort Order
Case Sensitivity
Null Value
Legacy Null
True Null Indexes
Rules for True Null Keys
NIS Values
Sorting of True Null Values
Linked Duplicate Keys and True Nulls
Repeating Duplicate Keys and True Nulls
Unique Keys and True Nulls
Nonmodifiable Keys and True Nulls
Get Operations and True Nulls
Distinct True Nulls
Multi-Segmented True Null Keys
Excluding Records from an Index
Use of Null Indicator Segment in Extended Operations.
True Nulls and the SQL Engine
True Nulls and Extended Operations
Alternate Collating Sequences
User-Defined ACS
International Sort Rules
Key Specification
Key Specification Block
Key Flag Values
Limitations and Side Effects
Database URIs
Syntax
Parameter Precedence
Precedence Examples
Special Characters
Examples
Remarks
Examples
IPv6
Double-Byte Character Support
Record Length
Data Integrity
Record Locks
Transactions
Exclusive Transactions
Concurrent Transactions
Exclusive vs. Concurrent
Transaction Durability
System Data
Shadow Paging
Backing Up Your Files
Event Logging
Performance Enhancement
System Transactions
Preparation Phase
Writing Phase
Frequency of System Transactions
Less Frequent
More Frequent
Memory Management
Page Preallocation
Extended Operations
Disk Usage
Free Space List
Index Balancing
Data Compression
Blank Truncation
Designing a Database
Understanding Data Files
Creating a Data File
Data Layout
Key Attributes
File Attributes
Creating File and Key Specification Structures
Sample Data Buffer for File and Key Specifications Using BTRV Entry Point
Creating a File with Page Level Compression
Calling the Create Operation
Create Operation
Create Index Operation
Calculating the Logical Record Length
Choosing a Page Size
Optimum Page Size For Minimizing Disk Space
Record Overhead in Bytes Without Record Compression
Record Overhead in Bytes With Record Compression
Page Overhead in Bytes
Physical Record Length Worksheet
Optimum Page Size Example
Minimum Page Size
Estimating File Size
Formula and Derivative Steps
Page Sizes of Special Pages by File Format
Optimizing Your Database
Duplicatable Keys
Linked-Duplicatable Keys
Repeating-Duplicatable Keys
Linked vs. Repeating
Page Preallocation
Blank Truncation
Record Compression
Index Balancing
Variable-tail Allocation Tables
Key-Only Files
Setting Up Security
Owner Names
Exclusive Mode
SQL Security
Language Interfaces Modules
Interface Modules Overview
Programming Notes
C/C++
Interface Modules
BTRAPI.C
BTRAPI.H
BTRVEXID.H
BTRCONST.H
BTITYPES.H
BTRSAMP.C
Programming Requirements
Delphi
DOS (Btrieve)
Interface Modules
BTRAPI.C
BTRAPI.H
BTRCONST.H
BTITYPES.H
Pascal
Source Modules
BBTRAPID.PAS
BTRCONST.PAS
BTRSAMPD.PAS
Visual Basic
Interface Libraries
Overview of Interface Libraries
Linux
Distributing Zen Applications
Distribution Rules for Zen
Installing Zen with your Application
Working with Records
Sequence of Operations
Accessing Records
Accessing Records by Physical Location
Physical Currency
Step Operations
Accessing Records by Key Value
Logical Currency
NCC Insert Operation
Get Operations
Reading Variable-Length Records
Get Equal Operation in C
Get Equal Operation in Visual BASIC
Accessing Records by Chunks
Intrarecord Currency
Chunk Operations
Inserting and Updating Records
Ensuring Reliability in Mission-Critical Inserts and Updates
Inserting Nonduplicatable Keys
Inserting and Updating Variable-Length Records
Insert Operation
Reading and Updating Fixed-length Portions
Updating Nonmodifiable Keys
No-Currency-Change (NCC) Operations
Multirecord Operations
Terminology
Background
Validation
Optimization
Examples
Performance Tips
Connectors
Reject Count
Adding and Dropping Keys
Supporting Multiple Clients
Btrieve Clients
Assumptions
Action Codes
Conflict Codes
Passive Concurrency
Record Locking
User Transactions
Locks
Explicit Record Locks in a Nontransactional Environment
Single-Record Locks
Multiple-Record Locks
When a Record Has Already Been Locked
Record Locks in Concurrent Transactions
Implicit Record Locks
Example Without Implicit Locks
Implicit Locks
File Locks
Examples of Multiple Concurrency Control
Example 1
Example 2
Concurrency Control for Multiple Position Blocks
Multiple Position Blocks
ClientID Parameter
Debugging Your Btrieve Application
Trace Files
MicroKernel Trace File of a BUTIL STAT Call
Indirect Chunk Operations in Client-Server Environments
Engine Shutdowns and Connection Resets
Reducing Wasted Space in Files
Btrieve API Programming
Fundamentals of Btrieve API Programming
Btrieve API Flow Chart
Inserting Records
Updating Records
Deleting Records
Visual Basic Notes
Delphi Notes
Starting a Zen Application
Adding Zen Source Modules
Btrieve API Code Samples
Creating a File
Sample Code
Visual Basic (Creating a File)
Delphi (Creating a File)
C/C++ (Creating a File)
Sample Structures (Creating a File)
Visual Basic (Creating a File) – Sample Structure
Delphi (Creating a File) – Sample Structure
C/C++ (Creating a File)– Sample Structure
Inserting Records
Sample Code
Visual Basic (Inserting Records)
Delphi (Inserting Records)
C/C++ (Inserting Records)
Sample Structures (Inserting Records)
Visual Basic (Inserting Records) – Sample Structure
Delphi (Inserting Records) – Sample Structure
C/C++(Inserting Records) – Sample Structure
Updating Records
Sample Code
Visual Basic (Updating Records)
Delphi (Updating Records)
C/C++ (Updating Records)
Sample Structures (Updating Records)
Visual Basic (Updating Records) – Sample Structure
Delphi (Updating Records) – Sample Structure
C/C++ (Updating Records) – Sample Structure
Performing Step Operations
Sample Code
Delphi (Step Operations)
C/C++ (Step Operations)
Sample Structures
Delphi (Step Operations) – Sample Structure
C/C++ (Step Operations) – Sample Structure
Performing Get Operations
Sample Code
Visual Basic (Get Operations)
Delphi (Get Operations)
C/C++ (Get Operations)
Sample Structures (Get Operations)
Visual Basic (Get Operations) – Sample Structure
Delphi (Get Operations) – Sample Structure
C/C++ (Get Operations) – Sample Structure
Chunking, BLOBs, and Variable-Length Records
Sample Code
Visual Basic (Chunking/BLOBs/Variable-Length Records)
Sample Structures (Chunking/BLOBs/Variable-Length Records)
Visual Basic (Chunking/BLOBs/Variable-Length Records) – Sample Structure
Working with Segmented Indexes
Sample Code
Visual Basic (Segmented Indexes)
Delphi (Segmented Indexes)
C/C++ (Segmented Indexes)
Declarations of Btrieve API Functions for Visual Basic
Creating a Database
Named Databases
Bound Databases
Creating Database Components
Naming Conventions
Unique Names
Valid Characters
Maximum Name Lengths
Case Sensitivity
Creating a Data Dictionary
Creating Tables
Aliases
Creating Columns
Creating Indexes
Index Segments
Index Attributes
Relational Database Design
Overview of Database Design
Stages of Design
Conceptual Design
Logical Design
Table Relationships
Normalization
First Normal Form
Second Normal Form
Third Normal Form
Keys
Physical Design
Inserting and Deleting Data
Overview of Inserting and Deleting Data
Inserting Values
Transaction Processing
Deleting Data
Dropping Indexes
Dropping Columns
Dropping Tables
Dropping an Entire Database
Modifying Data
Overview of Modifying Data
Modifying Tables
Setting Default Values
Using UPDATE
Retrieving Data
Overview of Retrieving Data
Views
Features of Views
Temporary and Stored Views
Read-Only Tables in Views
Mergeable Views
Selection Lists
Sorted and Grouped Rows
Joins
Joining Tables with Other Tables
Joining Views with Tables
Types of Joins
Equal Joins
Nonequal Joins
Cartesian Product Joins
Self Joins
Left, Right, Full Outer Joins
Subqueries
Subquery Limitations
Correlated Subqueries
Restriction Clauses
Restriction Clause Operators
Boolean Operators
Condition Operators
Expression Operators
Restriction Clause Examples
OR and Equal To (=)
IN
LIKE
Functions
Aggregate Functions
Arguments to Aggregate Functions
Aggregate Function Rules
Scalar Functions
Storing Logic
Stored Procedures
Stored Procedure and Positioned Update
Declaring Stored Procedures
Invoking Stored Procedures
Deleting Stored Procedures
SQL Variable Statements
Procedure-Owned Variables
Assignment Statements
SQL Control Statements
Compound Statement
IF Statement
LEAVE Statement
LOOP Statement
WHILE Statement
SQL Triggers
Timing and Ordering of Triggers
Specifying the Triggered Action Time
Specifying Trigger Order
Defining the Trigger Action
Managing Data
Overview of Managing Data
Defining Relationships Among Tables
Referential Integrity Definitions
Keys
Primary Keys
Creating Primary Keys
Dropping Primary Keys
Changing Primary Keys
Foreign Keys
Creating Foreign Keys in Existing Tables
Creating Foreign Keys When Creating a Table
Dropping Foreign Keys
Referential Constraints
Referential Integrity Rules
Insert Rule
Update Rule
Delete Rule
Anomaly on Delete-Connected Cycles
Anomaly on Multiple Paths
Referential Integrity in the Sample Database
Creating the Course Table
Adding a Primary Key to Course
Creating the Student Table with Referential Constraints
Administering Database Security
Understanding Database Rights
Establishing Database Security
Enabling Security
Creating User Groups and Users
Creating User Groups
Creating Users
Granting Rights
Granting Rights to the PUBLIC Group
Granting Rights to User Groups
Granting Rights to Users
Dropping Users and User Groups
Revoking Rights
Disabling Security
Retrieving Information about Database Security
Concurrency Controls
Transaction Processing
Starting and Ending Transactions
Using Savepoints to Nest Transactions
Special Considerations
Isolation Levels
Exclusive Isolation Level (SQL_TXN_SERIALIZABLE)
Cursor Stability Isolation Level (SQL_TXN_READ_COMMITTED)
Transactions and Isolation Levels
Avoiding Deadlock Conditions
Deadlock Conditions under Exclusive Isolation Level
Deadlock Conditions under Cursor Stability Isolation Level
Passive Control
Atomicity in Zen Databases
Transaction Control in Procedures
A. Sample Collations Using International Sorting Rules
German Sample Collations
Unsorted Data
Sorted Data
Spanish Sample Collations
Unsorted Data
Sorted Data
French Sample Collations
Unsorted Data
Sorted Data
B. Sample Database Tables and Referential Integrity
Overview of the Demodata Sample Database
Structure of the Demodata Sample Database
Assumptions
Entity Relationships
Example of Referential Integrity in the Demodata Database
Table Design of the Demodata Sample Database
BILLING Table
CLASS Table
COURSE Table
DEPT Table
ENROLLS Table
FACULTY Table
PERSON Table
ROOM Table
STUDENT Table
TUITION Table
About This Document
B. Sample Database Tables and Referential Integrity