What Is Dcl In Cobol?

DCLGEN (Declaration Generator) is a structure‑generating utility that maps the columns of a database table into a structure (a COBOL record) that can be included in an embedded SQL declaration section.

Why do we use Dclgen?

DCLGEN generates a table or view declaration and puts it into a member of a partitioned data set that you can include in your program. When you use DCLGEN to generate a table declaration, Db2 gets the relevant information from the Db2 catalog.

How Dclgen is created?

The easiest way to start DCLGEN is through DB2I. DCLGEN produces declarations for tables and views and the corresponding host variable structures for C, COBOL, and PL/I programs. DCLGEN derives the variable names and data types for these declarations based on the source tables in the database.

How do you declare a Dclgen in COBOL?

To include declarations from DCLGEN in your program: Code the following SQL INCLUDE statement in your program: EXEC SQL INCLUDE member-name END-EXEC. member-name is the name of the data set member where the DCLGEN output is stored.

What are host variables in COBOL?

Host variables are COBOL language variables that are referenced within SQL statements. Host variables allow an application to exchange data with the database manager. After the application is precompiled, host variables are used by the compiler as any other COBOL variable.

What is null indicator in COBOL DB2?

The null indicator is used by DB2 to track whether its associated column is null or not. A positive value or a value of 0 means the column is not null and any actual value stored in the column is valid.

Is Dclgen mandatory in COBOL?

Including the DCLGEN member is not mandatory until we explicitly give the host variables declaration in the working storage section.

What is cursor in DB2?

Db2 has a mechanism called a cursor . Using a cursor is like keeping your finger on a particular line of text on a printed page. In Db2, an application program uses a cursor to point to one or more rows in a set of rows that are retrieved from a table.

What is SPUFI and QMF?

QMF stands for Query Management Facility and SPUFI stands for SQL Processor Using File Input. Below are the differences between QMF and SPUFI. SPUFI is a free tool which comes with mainframe DB2 installation, while QMF is a separate licensed tool.

Why cursor is used in COBOL?

The CURSOR is used when we have to fetch multiple rows from a table. There are 4 steps involved in order to use a cursor in a COBOL-DB2 program. FETCH cursor− In this statement, we start fetching the data from DB2 and the row data is stored in host variables. The syntax is like below.

Is Sqlca mandatory in COBOL?

In COBOL, INCLUDE SQLCA must be specified in the Working-Storage Section or the Linkage Section. INCLUDE SQLCA must not be specified if the program is prepared (either with the Db2 precompiler or coprocessor) with the STDSQL(YES) SQL processing option. For a description of the SQLCA, see SQL communication area (SQLCA).

What is Sqlca in Db2?

SQLCA (SQL communication area)
An SQLCA is a set of variables that may be updated at the end of the execution of every SQL statement.

What is a Dbrm in Db2?

The contents of the DBRM represent the variables, framework, and generated SQL calls required by the Db2 system when processing the SQL commands sent from the z/TPF system.

What is payload variable?

Variables are used to store values to be consumed within a Mule application. Payload contains the data your Mule application processes. So maybe the question that will make sense is, “When to store the payload in a variable?” or vice versa.

What is Spufi in Db2?

SPUFI passes the input data set to Db2 for processing. Db2 executes the SQL statement in the input data set and sends the output to the output data set. The output data set opens. Your SQL statement might take a long time to execute, depending on how large a table Db2 must search, or on how many rows Db2 must process.

What is Comp 3 variables COBOL?

COBOL Comp-3 is a binary field type that puts (“packs”) two digits into each byte, using a notation called Binary Coded Decimal, or BCD. This halves the storage requirements compared to a character, or COBOL “display”, field.

What is type 2 index in DB2?

Type-2 index is an enhancement to the Type-1 index. It has numerous benefits. Creating index on tables is trial and error process i.e how many or what cloumns need to use for INDEX. As of DB2 V8 the Index Key size is 2,0000 Bytes. We need to avoid indexes on INSERT, DELETE and UPDATE.

What is deadlock in DB2?

A deadlock occurs when two or more application processes each hold locks on resources that the others need and without which they cannot proceed. After a preset time interval, Db2 can roll back the current unit of work for one of the processes or request a process to terminate.

Can primary key be null DB2?

Primary keys
A primary key is a special type of unique key and cannot contain null values.

Is stop run mandatory in COBOL?

Is STOP RUN mandatory in COBOL? Yes. STOP RUN is used to return control to the system, and it closes the tasks that are run by the program.

Is close cursor mandatory in DB2?

If you processed the rows of a result table and you do not want to use the cursor again, you can let the system close the cursor. The system automatically closes the cursor when: A COMMIT without HOLD statement is issued and the cursor is not declared using the WITH HOLD clause.