Application Programming and SQL Guide - Kmlinux

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Using the SQL communication area (SQLCA) . . . . . . . . . . . . 87
SQLCODE and SQLSTATE . . . . . . . . . . . . . . . . . . . 88
The WHENEVER statement . . . . . . . . . . . . . . . . . . . 88
Handling arithmetic or conversion errors . . . . . . . . . . . . . . 89
The GET DIAGNOSTICS statement . . . . . . . . . . . . . . . . 89
Calling DSNTIAR to display SQLCA fields . . . . . . . . . . . . . . 94
Chapter 7. Using a cursor to retrieve a set of rows . . . . . . . . . . 99
Accessing data by using a row-positioned cursor . . . . . . . . . . . . 99
Step 1: Declare the cursor . . . . . . . . . . . . . . . . . . . . 99
Step 2: Open the cursor . . . . . . . . . . . . . . . . . . . . 101
Step 3: Specify what to do at end-of-data . . . . . . . . . . . . . . 101
Step 4: Execute SQL statements . . . . . . . . . . . . . . . . . 102
Step 5: Close the cursor . . . . . . . . . . . . . . . . . . . . 104
Accessing data by using a rowset-positioned cursor . . . . . . . . . . . 104
Step 1: Declare the rowset cursor . . . . . . . . . . . . . . . . 104
Step 2: Open the rowset cursor . . . . . . . . . . . . . . . . . 104
Step 3: Specify what to do at end-of-data for a rowset cursor . . . . . . 105
Step 4: Execute SQL statements with a rowset cursor . . . . . . . . . 105
Step 5: Close the rowset cursor . . . . . . . . . . . . . . . . . 109
Types of cursors . . . . . . . . . . . . . . . . . . . . . . . . 109
Scrollable and non-scrollable cursors . . . . . . . . . . . . . . . 109
Held and non-held cursors . . . . . . . . . . . . . . . . . . . 118
Examples of using cursors . . . . . . . . . . . . . . . . . . . . 120
Chapter 8. Generating declarations for your tables using DCLGEN . . . . 127
Invoking DCLGEN through DB2I . . . . . . . . . . . . . . . . . . 127
Including the data declarations in your program . . . . . . . . . . . . 128
DCLGEN support of C, COBOL, and PL/I languages . . . . . . . . . . 129
Example: Adding a table declaration and host-variable structure to a library 130
Step 1. Specify COBOL as the host language . . . . . . . . . . . . 130
Step 2. Create the table declaration and host structure . . . . . . . . . 131
Step 3. Examine the results . . . . . . . . . . . . . . . . . . . 133
Chapter 9. Embedding SQL statements in host languages . . . . . . . 135
Coding SQL statements in an assembler application . . . . . . . . . . . 135
Defining the SQL communications area . . . . . . . . . . . . . . 135
Defining SQL descriptor areas . . . . . . . . . . . . . . . . . . 136
Embedding SQL statements . . . . . . . . . . . . . . . . . . 137
Using host variables . . . . . . . . . . . . . . . . . . . . . 139
Declaring host variables . . . . . . . . . . . . . . . . . . . . 139
Determining equivalent SQL and assembler data types . . . . . . . . 142
Determining compatibility of SQL and assembler data types . . . . . . . 146
Using indicator variables . . . . . . . . . . . . . . . . . . . . 147
Handling SQL error return codes . . . . . . . . . . . . . . . . . 148
Macros for assembler applications . . . . . . . . . . . . . . . . 149
Coding SQL statements in a C or C++ application . . . . . . . . . . . 149
Defining the SQL communication area . . . . . . . . . . . . . . . 149
Defining SQL descriptor areas . . . . . . . . . . . . . . . . . . 150
Embedding SQL statements . . . . . . . . . . . . . . . . . . 151
Using host variables and host variable arrays . . . . . . . . . . . . 152
Declaring host variables . . . . . . . . . . . . . . . . . . . . 153
Declaring host variable arrays . . . . . . . . . . . . . . . . . . 159
Using host structures . . . . . . . . . . . . . . . . . . . . . 164
Determining equivalent SQL and C data types . . . . . . . . . . . . 166
Determining compatibility of SQL and C data types . . . . . . . . . . 172
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