02:01
kareem
The ISNULL function returns whether a value is NULL. It is available in the Designer and the Workflow Manager.
The IS_DATE function returns whether a value is a valid date. It is available in the Designer and the Workflow Manager.
Example : The following expression checks the INVOICE_DATE port for valid dates:
IS_DATE( value, format )
If the format is not specified, ‘MM/DD/YYYY’ is taken as the default format.
The IS_NUMBER returns whether a string is a valid number. It is available in the Designer and the Workflow Manager.
The IS_SPACES function returns whether a value consists entirely of spaces. It is available in the Designer and the Workflow Manager.
IS_SPACES( value )
Example : The following expression checks the ITEM_NAME port for rows that consist entirely of spaces:
The DECODE function searches a port for the specified value. It is available in the Designer and the Workflow Manager.
Example: We might use DECODE in an expression that searches for a particular ITEM_ID and returns the ITEM_NAME:
DECODE( ITEM_ID, 10, 'Flashlight',
14, 'Regulator', 20, 'Knife', 40, 'Tank', 'NONE' )
The IIF function returns one of two values we specify, based on the results of a condition. It is available in the Designer and the Workflow Manager.
Example : IIF( SALES < 100, 0, SALARY )
IIF functions can be nested if there is more than one condition to be tested. But it is always a better option to go for DECODE function when the number of conditions is large since DECODE function is less costlier compared to IIF function.
For example consider the following expression
IIF(MARKS>=90,'A',
(IIF(MARKS>= 75,'B',
(IIF(MARKS>=65,'C',
(IIF(MARKS>=55,'D',
IIF(MARKS>=45,'E',
'F'))))))))
The same result can be obtained with
DECODE(TRUE,
MARKS>=90,'A',
MARKS>=75,'B',
MARKS>=65,'C',
MARKS>=55,'D',
MARKS>=45,'E',
'F')
When the number of conditions increase we will be able to appreciate the simplicity of the DECODE function and the complexity of the IIF function.
In both the cases , If MARKS>90 it will return 'A' though it satisfies all the conditions given. It is because it returns when the first condition is satisfied. Therefore even if a port satisfies two or more the conditions it will take only the first one. Therefore Ordering is important in IIF and DECODE functions.
The ERROR function causes the Informatica Server to skip a record and throws an error message defined by the user. It is available in the Designer.
ERROR( string )
Example : The following example shows how you can reference a mapping that calculates the average salary for employees in all departments of your company, but skips negative values. The following expression nests the ERROR function in an IIF expression so that if the Informatica Server finds a negative salary in the Salary port, it skips the row and displays an error:
The below example combines two special functions, a test Function and a conversion function.
IIF(IS_DATE(DATE_PROMISED,'MM/DD/YY'),TO_DATE(DATE_PROMISED),ERROR('Invalid Date'))
The LOOKUP function searches for a particular value in a lookup source column. It is available in the Designer.
LOOKUP( result, search1, value1 [, search2, value2]… )
Example : The following expression searches the lookup source :TD.SALES for a specific item ID and price, and returns the item name if both searches find a match:
Posted by flyingcolors at 12:28 AM 0 comments Links to this post
Labels: Functions in Informatica
Date Format Strings in the Transformation Reference
Days (01-31). We can use any of these format strings to specify the entire day portion of a date. For example, if we pass 12-APR-1997 to a date function, we can use any of these format strings specify 12.
Hour of day (0 to 23), where zero is 12 AM (midnight). We can use any of these formats to specify the entire hour portion of a date. For example, if we pass the date 12-APR-1997 2:01:32 PM, we can use HH, HH12, or HH24 to specify the hour portion of the date.
Month portion of date (0 to 59). We can use any of these format strings to specify the entire month portion of a date. For example, if we pass 12-APR-1997 to a date function, we can use MM, MON, or MONTH to specify APR.
Second portion of date (0 to 59).
Year portion of date (1753 to 9999). We can use any of these format strings to specify the entire year portion of a date. For example, if we pass 12-APR-1997 to a date function, we can use Y, YY, YYY, or YYYY to specify 1997.
The ADD_TO_DATE function adds a specified amount to one part of a date/time value, and returns a date in the same format as the specified date.
Note: If we do not specify the year as YYYY, the Informatica Server assumes the date is in the current century. It is available in the Designer and the Workflow Manager.
Example : The following expression adds one month to each date in the DATE_SHIPPED port. If we pass a value that creates a day that does not exist in a particular month, the Informatica Server returns the last day of the month. For example, if we add one month to Jan 31 1998, the Informatica Server returns Feb 28 1998.
Also note, ADD_TO_DATE recognizes leap years and adds one month to Jan 29 2000:
| DATE_SHIPPED | RETURN VALUE |
ADD_TO_DATE( DATE_SHIPPED, 'D', -10 )
In ADD_TO_DATE function, if the argument passed evaluates to a date that does not exist in a particular month, the Informatica Server returns the last day of the month.
The following expression reveals this.
ADD_TO_DATE( DATE_SHIPPED, 'MON', 3 )
| DATE_SHIPPED | RETURN VALUE |
| Jan 31 1998 6:24:45PM | Apr 30 1998 6:24:45PM |
The DATE_COMPARE function returns a value indicating the earlier of two dates. It is available in the Designer and the Workflow Manager.
Example : The following expression compares each date in the DATE_PROMISED and DATE_SHIPPED ports, and returns an integer indicating which date is earlier:
The DATE_DIFF function returns the length of time between two dates, measured in the specified increment (years, months, days, hours, minutes, or seconds). It is available in the Designer and the Workflow Manager.
Example: The following expressions return the number of days between the DATE_PROMISED and the DATE_SHIPPED ports:
We can combine DATE functions and TEST functions so as to validate the dates.
For example, while using the DATE functions like DATE_COMPARE and DATE_DIFF, the dates given as inputs can be validated using the TEST function IS_DATE and then passed to them if valid.
The GET_DATE_PART function returns the specified part of a date as an integer value, based on the default date format of MM/DD/YYYY HH24:MI:SS. It is available in the Designer and the Workflow Manager.
Example: The following expressions return the day for each date in the DATE_SHIPPED port:
The LAST_DAY function returns the date of the last day of the month for each date in a port. It is available in the Designer and the Workflow Manager.
Example : The following expression returns the last day of the month for each date in the ORDER_DATE port:
DATE functions combine with Conversion functions also.
The following expression has LAST_DAY and TO_DATE functions nested or combined together.
LAST_DAY( TO_DATE( GIVEN_DATE, 'DD-MON-YY' ))
We can return the maximum date for a port or group.
Example: The following expression returns the maximum order date for flashlights:
Example: The following expression returns the oldest order date for flashlights:
| |
The ROUND function rounds one part of a date. It is available in the Designer and the Workflow Manager.
Similarly the ROUND function can be used to round off Year, Day or Time portions.
The SET_DATE_PART function sets one part of a date/time value to a specified value. It is available in the Designer and the Workflow Manager.
Example: The following expressions change the month to June for the dates in the DATE_PROMISED port. The Informatica Server displays an error when we try to create a date that does not exist, such as changing March 31 to June 31:
Similarly the SET_DATE_PART function can be used to round off Year, Day or Time portions.
The TRUNC function truncates dates to a specific year, month, day, hour, or minute. It is available in the Designer and the Workflow Manager.
Similarly the TRUNC function can be used to truncate Month , Day or Time portions.
The functions TRUNC & ROUND can be nested in order to manipulate dates.
Posted in: Informatica Functions
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