What is meant by LLD and HLD in a project

spriya · New User Joined: 06 Oct 2005 Posts: 42

can anyone explain my queries?

How we will compile thru endevor?
How we will load our sequential file to table?
What is a null indicator?
What is meant by LLD and HLD in a project?

iknow · Posted: Sun Dec 04, 2005 11:35 am

Hi spriya,

For your 3rd query, check the answers below.

A group level item will contain all the NULL indicators for each column in the table. This group level name will be '-NULL' appended to 'DCL' concatenated with the table name.

Example

--------------------------------------------------------------

COBOL DECLARATION FOR TABLE authors

--------------------------------------------------------------

01 DCLauthors.

03 au-id PIC X(11).

03 au-lname PIC X(40).

03 au-fname PIC X(20).

03 phone PIC X(12).

03 address PIC X(40).

03 city PIC X(20).

03 state PIC X(2).

03 zip PIC X(5).

03 contract PIC S9(04) COMP-5.

--------------------------------------------------------------

COBOL INDICATOR VARIABLES FOR TABLE

--------------------------------------------------------------

01 DCLauthors-NULL.

03 address-NULL PIC S9(04) COMP-5.

03 city-NULL PIC S9(04) COMP-5.

03 state-NULL PIC S9(04) COMP-5.

03 zip-NULL PIC S9(04) COMP-5.

Hope this helps...

For rest of your queries please specify your queries in detail.

mak_tcs · Posted: Mon Dec 05, 2005 8:47 pm

Hi priya,

Somewhere i heard of LLD and HLD;

LLD - Low Level Design

LLD is like a Overall Functional view of a Project.

HLD - High Level Design

HLD is Technical or Implementation view(detailed) of a Project

Thanks,
Mani

vishal_a · New User Joined: 24 May 2005 Posts: 45 Location: Noida

hi priya,

LLD --->Stands for Low Level Design. Its basically the implementation details regarding the problem at low level as if the description.

HLD ---> High level design . Basically we also call it as Tech Spec or Technical Specification. It contains the logic or the condition , what to do in the problem . What steps to follow in the coding.

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Endevor takes care for compiling for us only we have to specify the batch language for it or the compiling language for it.

------------------------------------------------

suman_236 · New User Joined: 18 Nov 2005 Posts: 11 Location: Chennai

Priya -

All the member gave some good replys for your queries..i'm adding some more info.....

How we will compile thru endevor?
Compiling thru Endevor is very simple process becos Endevor takes care of creating the jcl with the compile options and link-edit options.

All the user has to do is specify the options you want to use for compiling the program. Endevor then creates a SCL. A SCL basically contains the options you want to use for compiling the program. Using the SCL, Endevor submits a batch job whihc compiles the program.

How we will load our sequential file to table?
You can use SOFTTECH tool for loading a file into a table. In SOFTECH tool, look for 'MIGRATION option'.

What is a null indicator?

See the below Db2 query

SELECT MAX(AMOUNT)
INTO :WS-AMOUNT :WS-NULL-IND
FROM PRICE_TABLE

Select queries with MAX, MIN, SUM ...etc functions never return SQLCODE of 100, even if no row found is found in the Table.

In the above query, if no row is found in PRICE_TABLE, this query will return SQLCODE = 0 and populates low values in WS-AMOUNT. If you use WS-AMOUNT(populated with low values) in any calculation, the program will abend with S0C7.

Since the return SQLCODE is 0 even if no row is found in the table, there is no way to know if WS-AMOUNT contains valid value or low-values.

Null-indicator is used to solve this. WS-NULL-IND variable in the above query is called the Null-indicator. This variable is set to positive value if some rows are found for the query. If no row is found is found, it is set to 0 or negative value. This way you can prevent S0C7 abends.

What is meant by LLD and HLD in a project?

HLD - is the high level design. This is the design of the project in the broader sense.
This shows how different processes in the project interact with each other. In HLD, a process are shown as black box..i.e no desciption is provided as to the internal logic of the process.

LLD - is the low level design. It describes a process in detail. I think there is no limit to how much detail the LLD can be.

Hope this info was useful......if any doubts, send me.

superk · Posted: Tue Dec 06, 2005 7:38 pm

Are these two terms - LLD and HLD - unique to a specific industry or company, or are they some new terms that someone has recently created?

I'm sure that I'm not the only one who has never heard of them before. My thought was that they might have stood for "Low Level Diagnostics" and "High Level Diagnostics", although the online acronym finder mentions "Low Level Design" and "High Level Design". However, it offers no definitions of these terms.

suman_236 · New User Joined: 18 Nov 2005 Posts: 11 Location: Chennai

HLD and LLD have been around for quite sometime. May be, they are relatively new!

are you familiar with Waterfall model? HLD is oucome of Business design phase. LLD is the outcome of Technical design phase.