Technology Questions

- ABS(number)

Returns the absolute positive value of an expression.
Syntax:
ABS(expression)
Example:
SELECT ABS(-1.0), ABS(0.0), ABS(1.0)
Output:
1.0    .0    1.0

- CEIL(number)

Returns the smallest integer greater than, or equal to, the specified numeric expression.
Syntax:
CEILING(expression)
Example:
SELECT CEILING($223.45), CEILING($-223.45), CEILING($0.0)
Output:
224.00    -223.00        0.00

- FLOOR(number)

Returns the largest integer less than, or equal to, the specified numeric expression.
Syntax:
FLOOR(expression)
Example:
SELECT FLOOR($223.45), CEILING($-223.45), CEILING($0.0)
Output:
223.00      -224.00        0.00

- MOD(number, divisor)

Returns the remainder of the division from 2 integer values.
Syntax:
MOD(dividend, divisor)
Example:
SELECT MOD(20,3)
Output:
2

- POWER(number, power)

Returns the exponential value for the numeric expression.
Syntax:
POWER(number, power)
Example:
SELECT POWER(2.0, 3.0)
Output:
8.0

- SIGN(number)

Returns the sign i.e. positive or negative value for the numeric expression. It returns -1 for negative expressions, a value of 0 for zero
Syntax:
SIGN(number)
Example:
SELECT SIGN(4)
Output:
1

- ROUND(number, precision)

Returns the numeric value rounded off to the next value specified.
Syntax:
ROUND(number, number of places)
Example:
SELECT ROUND(1.3456, 2)

- SQRT(number)

Returns the square root value of the expression.
Syntax:
SQRT(number)
Example:
SELECT SQRT(4.0)
Output:
2.0

- TRUNC(number, precision)

Returns a numeric value that truncate to the specific places
Syntax:
TRUNCATE(number,places)
Example:
SELECT TRUNCATE(1.3456, 2)
Output:
1.34

Following guidelines to be following while writing Cobol program:

- Use ? EVALUATE ? statement for constructing cases.

- Use scope terminators for nesting.

- Use in-line Perform statement for writing ?do? constructions.

- Use Test Before and Test After in the Perform statement while writing Do-While statements.

1. Operational Data Store has very low data latency. Data moved to ODS mostly on event based rather than time based ETL to Data Warehouse/Data Mart. 

2. ODS is more closer to OLTP system. We don't normally prefer to store aggregated data in OLTP. So it is with ODS. 

3. Unlike data warehouse where data is HISTORICAL, ODS is near real time(NRT). So data aggregation is less important is ODS as data keeps changing.

The LOAD command retrieves an object program from disk and loads it into main storage - it's primarily used for a constant table that will be available system-wide.

- By using method overriding a sub class can change the definition of super class method.

- By using overriding a sub class can modify the functionality of the super class.

The LMHOSTS file is a static method of resolving NetBIOS names to IP addresses in the same way that the HOSTS file is a static method of resolving domain names into IP addresses. An LMHOSTS file is a text file that maps NetBIOS names to IP addresses; it must be manually configured and updated.

<?php
$tomorrow = mktime(0, 0, 0, date("m") , date("d")+1, date("Y"));
$lastmonth = mktime(0, 0, 0, date("m")-1, date("d"), date("Y"));
echo ($tomorrow-$lastmonth)/86400;
?>

A collection just like an array is an ordered group of elements of the same type. Each elements position is determined by a unique subscript.

Index by tables:- They are similar to hash arrays that allows to search for subscript values using arbitrary numbers and strings.

They can be declared as:

TYPE type_name IS TABLE OF element_type [NOT NULL]

INDEX BY [BINARY_INTEGER | PLS_INTEGER | VARCHAR2(size_limit)];

INDEX BY key_type;

Example:

TYPE studenttyp IS TABLE OF emp%ROWTYPE

INDEX BY BINARY_INTEGER;

stud_tab studenttyp;

Nested tables:- they hold random number of elements and use sequential numbers as sub scripts.

They can be declared as:

TYPE type_name IS TABLE OF element_type [NOT NULL];

Example: TYPE employee_type IS TABLE OF NUMBER INDEX BY VARCHAR2(64);

Varrays: Holds a fixed number of elements which can be changed in run time. 

They can be declared as:

TYPE type_name IS {VARRAY | VARYING ARRAY} (size_limit) OF element_type [NOT NULL];

Example: TYPE Calendar IS VARRAY(366) OF DATE;