DECODE has one specific "feature": it considers two null values to be the same. You're looking for a Dictionary<int, string>. select empno,ename,job,mgr,hiredate,sal,nvl (comm,0),deptno,city from emp. For example: You could use the decode function in an SQL statement as follows: The above decode statement is equivalent to the following IF-THEN-ELSE statement: IF supplier_id = 10000 THEN. NVL () Examples. Can i able to overload the function by just changing the return type from boolean to number. SELECT DECODE (Letters, 'First',1, 'Second',2, 'Third',3, 0) AS LN. i2c_arm bus initialization and device-tree overlay. Oracle Function Example. . In the above example dept_no is expression. One of the most amazing features of the case the Oracle decode statements is that they allow us to create an index on data column values that do not exist in the database. 0.05 seconds Another Oracle Function Example. We can use the NVL function to replace NULL values for COMM with 0 by giving the following command. Prior to 11g, we can get the same result using the DECODE function and a pivot table with the correct number of rows. rev2022.12.11.43106. The default value ( 'Jim' ) will be returned if no matches are found. Oracle DECODE is use for transform the data to one value to another value. FROM LettersTable. The argument after that will be comparing the values of the first argument with it. The first argument in the decode statement will be generally some column where data transformation is needed. Let's see the following example: SELECT DECODE ( 1, 1, 'Equal' ); Code language: SQL (Structured Query Language) (sql) In this example, the DECODE () function compares the first argument (one) with the second argument (also one). DECODE( expression_id , search_id , result_id [, search , result]. Now, you can run this function and it will give you the results that you need. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. i.e,. The following shows the syntax of the NVL () function: NVL (e1, e2) Code language: SQL (Structured Query Language) (sql) The NVL () function accepts two arguments. If default is omitted, then Oracle returns null. Where does the idea of selling dragon parts come from? Now write another program to call the function. It can be declared and defined at a same time or can be declared first and defined later in the same block. Decode function vs Case statement in PL-SQL - Learn how to use Decode function and Case statements in the situations where you need to use decision making statements with IF -THEN - ELSE logic with example programs.. DECODE and CASE both provides IF-THEN-ELSE functionality in Oracle SQL. (2) CASE can work as a PL/SQL construct but DECODE is used only in SQL statements.CASE can be used as a parameter of a function/procedure. It can be one or a combination of the following values: Last 3, 2, or 1 digit (s) of year. Number Functions (also known as Math Functions) Number functions accept numeric input and return numeric values. Why do some airports shuffle connecting passengers through security again. Decode function is similar to if else statements and hence it simplifies code. This is the "select expression". The key concept here is DATATYPE, not 'type', not 'data type', but 'datatype'. How do I encode and decode a base64 string? Would like to stay longer than 90 days. http://www.techonthenet.com/oracle/functions/decode.php. SUBSTR () Examples. JavaTpoint offers too many high quality services. However all cases are now considered which is MUCH better programming practice. Let us look at the examples for ORACLE LENGTH( ) function for getting a better understanding of different cases where we can use the function. Download Oracle Sample Database Create Oracle Sample Database Connect To Oracle Database Server Oracle Data Manipulation SELECT Oracle DUAL Table ORDER BY SELECT DISTINCT WHERE Table & Column Aliases AND OR FETCH BETWEEN IN LIKE IS NULL Joins INNER JOIN LEFT JOIN RIGHT JOIN FULL OUTER JOIN CROSS JOIN Self Join GROUP BY HAVING UNION INTERSECT MINUS Example: Code: SELECT DECODE (1, 1, 'One') FROM dual; Output: The simple illustration of the above mentioned decode function is as follows: Code: IF 1 = 1 THEN result = 'One' ENDIF; Examples of SQL DECODE () Given below are the examples mentioned: A value between 0-49 will return a 20xx year. It will help you (and whoever has to maintain the code) as well as the people who want to help you. I tested it and this is the correct syntax and it returns 01-AUG-11. Example: SELECT name, DECODE ( student_id, 1, 'Tom', 2, 'Mike', 3, 'Harry' , 'Jim') result FROM students; Explanation: Here, each student_id value will be compared one by one by the DEFAULT function. Because the first argument equals the second one, the function returns the third argument which is the string Equal. The decode always returns the date format in DD-MMM-YY format whereas I want it to return in MM/DD/YYYY format. Learn how to use it in this article. SELECT TO_CHAR (SYSDATE, 'MM/DD/YYYY') FROM DUAL; Unfortunately, we get '000000' at times. Not exactly the same, but not too bad either: Thanks for contributing an answer to Stack Overflow! Now let's start understanding the usage of this function. Let's take an example to demonstrate Declaring, Defining and Invoking a simple PL/SQL function which will compute and return the maximum of two values. [, default] ) Parameters or arguments. Aggregate functions like SUM (), COUNT (), MAX (), MIN (), etc. So, in this example, we are going to create a function that is going to return the employee . So i have to create another similar function that returns Number instead of boolean. DECODE. SELECT (columns list) FROM AGREEMENT A WHERE A.ACCOUNT = 545 AND A.GRP_ID = DECODE (?, 0, A.GRP_ID, ?) The next step is to specify a value that the expression could return. 2 Answers. Of course and easier way to write this would be: to oracle@googlegroups.com, Oracle@googlegroups.com, http://groups.google.com/group/Oracle-PLSQL?hl=en, http://groups.google.com/group/Oracle-PLSQL?hl=en-, http://groups.google.com/group/Oracle-PLSQL?hl=en-Hide. The Oracle database outputs a corresponding result if the expression equals the search value. When a subprogram calls itself, it is called recursive call and the process is known as recursion. My sql works except it is returning the valid dates in the wrong format. If we wanted to say that if the department is Sales, then the result is Group A, our function might look like this: Now, if we wanted, we can add a closing bracket and end the function. INSTR. I would use CASE for a question like this where you're evaluating a boolean condition. Ready to optimize your JavaScript with Rust? It will calculate the number of months between two dates, as a decimal number. In case you don't know, DUAL is a table that has one column and one row. How do I put three reasons together in a sentence? Oracle/PLSQL syntax of the DECODE function. You already know that a program or a subprogram can call another subprogram. Does illicit payments qualify as transaction costs? DECODE Function in Oracle with Example || Oracle Database Tutorial || Database Interview question, Learn Oracle | Using Case Function, Decode Function in SQL, What is the difference between decode and case, SQL tutorial 51: DECODE function in Oracle Database By Manish Sharma (RebellionRider), Oracle SQL Video Tutorial 27 - DECODE function, Tutorial 34 : Oracle DECODE Function Explained. Does integrating PDOS give total charge of a system? Making statements based on opinion; back them up with references or personal experience. For example, if you wanted to check the department of an employee, and show different values depending on the department, then the department would be the expression. So, that's how you use the DECODE function in Oracle. The maximum number of components in the DECODE function, including expr, searches, results, and default, is 255. The select expression is typically a column, but can be a subquery, literal, or other expression. How would you create a standalone widget from this widget tree? Some other interesting date difference/compare techniques here: http://www.orafaq.com/faq/how_does_one_get_the_time_difference_between_two_date_columns. The functionality of DECODE in ORACLE with following flowchart. In the following example, the Oracle DECODE () function compares the first argument (1) with the second argument (1). If you are getting '000000' then your example is not showing what you are actually doing. How to change background color of Stepper widget to transparent color? @Allan has already given you the best solution to me, but if you insist on using decode function, you can process the result of sign function instead. Is it appropriate to ignore emails from a student asking obvious questions? SYSDATE This function returns the current date and time of the Operating system in which the Oracle database is installed. Syntax. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Let's take a customer table. Learn how to use it in this article. I've used something like that before as well, so translating status numbers to text values is a good example. Which is better decode or case in Oracle? This Oracle tutorial explains how to use the Oracle / PLSQL SIGN function with syntax and examples. Decode,Case Function with Syntax and usages : 1.Both oracle function and oracle case functions are important functions which are used to transform the values from single value to another separate value. Share Improve this answer FAQ about Oracle sql Decode processing In SQL Server, you can use CASE expression that is also supported by Oracle. DECODE function allows us to add procedural if-then-else logic to the query. Oracle DECODE is a function in Oracle which help to implement if-then-else logic in SQL query. You can specify a default value by adding a default parameter. Anyway, I will wait until tomorrow to get the right syntax and post it again. DECODE(status, 1 . Any built in method ? In this example, we will have two steps. I know i can use if else if structure or switch but then i need to do it dynamically.Please share some logical steps for creating one if not there. The function knows this is the default parameter. However, it replaces a single character at a time. What is this fallacy: Perfection is impossible, therefore imperfection should be overlooked. Unfortunately the DECODE only handles the positive result: SQL> select DECODE (SIGN (TO_DATE ('&pdate', 'DD/MM/RRRR') - (TO_DATE('10/02/2014','DD/MM/RRRR'))), 1, 'A') from dual; Not really a good strategy. Oracle NVL2 () function examples Let's take some examples of using the Oracle NVL2 () function to understand how it works. Thanks for your help. How to convert DateTime to string in C# using Oracle date format. This is the next parameter - the search parameter. The syntax for the GREATEST function in Oracle/PLSQL is: GREATEST( expr1 [, expr2, . For example, we want to return the first 5 characters from the string "United States". Dual EU/US Citizen entered EU on US Passport. The first part of using the DECODE function is to write the expression, which is the first parameter. While the Oracle decode () function compares an expression to every search item one by one. Let's take an example to demonstrate Declaring, Defining and Invoking a simple PL/SQL function which will compute and return the . To learn more, see our tips on writing great answers. ie. Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. For example, suppose we have table: emp, with the following structure. Asking for help, clarification, or responding to other answers. Notice we just added the single option at the end. In the following example we use the CONNECT BY clause in a query from dual to generate the correct number of rows for the unpivot operation. If STATE is equal to 'HI', then the DECODE function returns the literal shown here. JavaTpoint offers college campus training on Core Java, Advance Java, .Net, Android, Hadoop, PHP, Web Technology and Python. Oracle DECODE function is used in different database versions like Oracle 9i,Oracle 10g,Oracle 11g and Oracle 12c. Want the similar functionality in C# language. You must have define some parametrs before creating a procedure or a function. An old question, but since it got pulled out of obscurity by another answer, here is how I would try to replicate the decode function in C#. The first case looks at the value in STATE and compares it to this value (the literal 'HI'). could be rewritten using decode in the following way: You could try the months_between function. If you want to remove your created function from the database, you should use the following syntax. Tests whether a given character occurs in the given string or not. you can not make a DATE have a value of zeros. This example calculates the factorial of a given number by calling itself recursively. How does legislative oversight work in Switzerland when there is technically no "opposition" in parliament? This function works like a NULL safe CASE expression. DECODE Function Oracle APEX Release 22.2 API Reference 30.3 DECODE Function This function decodes a raw token value. This is the format that will be used to convert string1 to a date. Mail us on [emailprotected], to get more information about given services. 2. Raises VALUE_ERROR: The input value is invalid. Let's see a simple example to create a function. Possibly you understand the DECODE and SIGN functions now. Examples to Implement LENGTH( ) Function in Oracle. Pivot function or clause was introduced in 11g before that oracle decode function was used. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. I found this article - http://www.techonthenet.com/oracle/functions/decode.php. Thus, the following logic. Which value it returns depends on whether the value is positive (1), zero (0) or negative (-1): SQL> select SIGN (TO_DATE ('&pdate', 'DD/MM/RRRR') - (TO_DATE('10/02/2014','DD/MM/RRRR'))) from dual; SIGN(TO_DATE('01/02/2012','DD/MM/RRRR')-(TO_DATE('10/02/2014','DD/MM/RRRR'))), SIGN(TO_DATE('10/02/2014','DD/MM/RRRR')-(TO_DATE('10/02/2014','DD/MM/RRRR'))), SIGN(TO_DATE('10/04/2014','DD/MM/RRRR')-(TO_DATE('10/02/2014','DD/MM/RRRR'))). Counterexamples to differentiation under integral sign, revisited. In Oracle, you can use DECODE function to evaluate a list of expressions, and if a value is matched return the corresponding result. This is the result parameter. That function will return date2 if date2 <= date1. DECODE Function Syntax and More Information. Explanation of an example of the DECODE function The column the DECODE function examines is named STATE. Solution 1. "Data Type Comparison Rules" for information on comparison semantics SQL> SELECT id, DECODE (col1, NULL, 'ZERO', col1) AS output FROM null_test_tab ORDER BY id; ID OUTPUT ---------- ---------- 1 ONE 2 ZERO 3 ZERO 4 ZERO 4 rows selected. 2. Not exactly the same, but not too bad either: public static TOutput Decode<TInput, TOutput> (TInput expression, params Tuple<TInput, TOutput . MOSFET is getting very hot at high frequency PWM. So, if we wanted to return a value of No Group if no match was found, we can do this: DECODE (department, Sales, Group A, Marketing, Group B, IT, Group A, No Group). There may be performance improvements if you have the most common values earlier in the function. The first step is going to be the creation of the function in the database and the second step is going to be the execution of the function by calling the function and passing input parameters with the function. If you're trying to check by date - that is, every time in 1/1 is less than 1/2, and every on 1/1 is equal to every other time on 1/1, even if the Oracle DATE is greater - then you want to compare as follows: I don't see this in the other answers, it is so basic it makes me wonder if I'm misunderstanding the question. This is why I use decode to change the zeros to null. SELECT SUBSTR ("United States",1,5) FROM dual; SUBST --------- Unite. This example illustrates creating and calling a standalone function. decode(to_date(to_char(SYSDATE,'YYYYMM'),'YYYYMM'),'000000',null,to_date(to_char(SYSDATE, > > On Thu, Aug 11, 2011 at 9:03 PM, Michael Moore <, > >> On Thu, Aug 11, 2011 at 5:45 PM, Jyothi Kavasseri <, I am just using SYSDATE as an example only since SYSDATE can never be, > If you are getting '000000' then your example is not showing what you are. The Oracle DECODE () function allows you to add the procedural if-then-else logic to the query. Changes in This Release for Oracle Database SQL Language Reference 1 Introduction to Oracle SQL 2 Basic Elements of Oracle SQL 3 Pseudocolumns 4 Operators 5 Expressions 6 Conditions 7 Functions About SQL Functions Single-Row Functions Aggregate Functions Analytic Functions Object Reference Functions Model Functions OLAP Functions DECODE compares the expression to each search value one by one. Arguments expr. One of our readers suggested combining the SIGN function with the DECODE function as follows: The example with the dates above can be modified as follows: DECODE (SIGN (date1-date2), 1, date2, date1) The combination of SIGN / DECODE is also useful for digital comparisons such as bonus sales. The Oracle NVL () function allows you to replace null with a more meaningful alternative in the results of a query. This is the value that is checked against for the entire function. SQL> select to_date('20110809','yyyymmdd') from dual, SQL> select to_date('00000000','yyyymmdd') from dual, select to_date('00000000','yyyymmdd') from dual. How to check if widget is visible using FlutterDriver. Because they are equal, the function returns the third argument which is the string 'One': SELECT DECODE ( 1, 1, 'One' ) FROM dual; 2 Minute Read. In a DECODE function, Oracle considers two nulls to be equivalent. Searches a port for a value you specify. Or, if you want to be more succinct, you could use the function that's designed to return the lower of n values: (There is also a GREATEST function, which does the opposite.). Applies to Open Source Edition Express Edition Professional Edition Enterprise Edition. The following query tests whether the character "a" occurs in string "mohammed sami". Oracle/PLSQL DECODE function has functionality of IF-THEN-ELSE operator. In Oracle decode (), the default value is returned if no match is found and . 7.9K Oracle Database Express Edition (XE) 3.1K ORDS, SODA & JSON in the Database; 575 SQLcl; 4K . Now, when the department value is equal to Sales, what should happen? How to read decode in Oracle. expr_n] ) Parameters or Arguments expr1 The first expression to be evaluated whether it is the greatest. If expression is equal to a search, then the corresponding result is returned by the Oracle Database or If a match is not found, then default is returned. After the execution of above code, you will get the following result. http://www.orafaq.com/faq/how_does_one_get_the_time_difference_between_two_date_columns, http://www.techonthenet.com/oracle/functions/decode.php, TabBar and TabView without Scaffold and with fixed Widget. Plugging in the values and translating to pseudo-code, you get if 0 - 0 = 0 then date2 else date1 where both dates are the same. Please Share If you compared the DECODE statement to an IF statement, such as IF a=b, then it's one side of the IF statement. 2) the entire DECODE function could simply be replaced by (date1 > date2) Consider the following example: In case you don't know, DUAL is a table that has one column and one row. These are all of the mandatory parameters. The working of the above decode function is internally similar to following if-else condition - IF 500=600 THEN RETURN "Five Hundred" ELSE RETURN NULL END IF; Example #3 We can also provide more than one search expression for comparison; in that case, our decode function will be behaving the same as that of the if-else if ladder. Example DECLARE V_x VARCHAR2(10) := 'A'; V_y VARCHAR2(10); BEGIN V_y := CASE V_x WHEN 'A' THEN 'Excellent' WHEN 'B' THEN 'Good' WHEN 'C' Then 'Average' ELSE 'Poor' END; DBMS_OUTPUT.PUT_LINE( Radial velocity of host stars and exoplanets. jOOQ supports the DECODE () function and emulates . Sample code select id, decode (status,'A','Accepted','D','Denied','Other') from contracts; Will return for each id: If status = 'A' : 'Accepted' If status = 'D' : 'Denied' Else : 'Other' Oracle automatically converts the values for expression and compare_value to the datatype of the first compare_value. DECODE allows you to add many more. In this example, the Decode function compares the first and second arguments. search_id - value that is compared to. The Oracle/PLSQL TRANSLATE function replaces a sequence of characters in a string with another set of characters. Why does the USA not have a constitutional court? 5 Total Steps You're looking for a Dictionary. When should i use streams vs just accessing the cloud firestore once in flutter? LENGTH OF A STRING: In this case we will pass a string constant inside the parenthesis of the length function. DECODE Function Help Center Oracle Application Express API Reference Database Oracle Application Express Release 19.1 API Reference Table of Contents Search Download Table of Contents Title and Copyright Information Preface Changes in This Release 1 APEX_APPLICATION 2 APEX_ACL 3 APEX_APPLICATION_INSTALL 4 APEX_AUTHENTICATION 5 APEX_AUTHORIZATION Oracle DECODE only use for equality check logic in Oracle SQL. Equivalent of Oracle DECODE function in C#. Let's take an example to calculate the factorial of a number. In this condition, if doc status is "R" and parameter date minus 10feb2014 is positive figure then doc status will be considered as authorised "A", You do not have permission to delete messages in this group, Either email addresses are anonymous for this group or you need the view member email addresses permission to view the original message. If expr is null, then Oracle returns the result of the first search that is also null. Although DECODE is very powerful, how it works is actually very easy to understand: It compares the expression passed in as the first argument, to each of the search values passed in subsequent arguments, one by one, and if it finds a match, returns the corresponding result, otherwise returns the default value. The Oracle / PLSQL SIGN function returns a value indicating the sign of a number. MySQL decode () function decodes the encoded string and outputs an original string. Is MethodChannel buffering messages until the other side is "connected"? The second case is considered if STATE does not contain 'HI.' Answer: To accomplish this, use the DECODE function as follows: DECODE ( (date1 - date2) - ABS (date1 - date2), 0, date2, date1) The formula below would equal 0, if date1 is greater than date2: (date1 - date2) - ABS (date1 - date2) Helpful Tip #1: One of our viewers suggested combining the SIGN function with the DECODE function as follows: The DECODE function is not specifically for handling null values, but it can be used in a similar way to the NVL function, as shown by the following example. If you use DECODE to search for a value in a string port, you can either trim trailing blanks with the RTRIM function or include the blanks in the . You can build an unlimited number of searches within a DECODE function. But, that doesn't explain the DECODE statement, so let's take it apart. After the execution of above code in SQL prompt, you will get the following result. Using the earlier example, if one of the departments was Sales, then your statement could look like this: The function still needs a bit more to make it usable. You can, if you need to, add more pairs of the search value and result value. Hi All- I have a requirement where i need to convert a case statement into a nested decode statement here is the scenario . Using flutter mobile packages in flutter web. Why do we use perturbative series if they don't converge? If I want to compare A and B and I want nulls to be considered "the same", I prefer where decode (A,B, 0, 1) = 0 to where nvl (A, <something>) = nvl (B, <something>) or where A = B or (A is null and B is null) In SQL Server the equivalent code is CASE statement. Note that NULL values in DECODE function and CASE expression are handled differently . All rights reserved. How can you know the sky Rose saw when the Titanic sunk? WHEN Y.DOC_STATUS = 'R' AND DECODE (SIGN (TO_DATE (:P_CHK_RECD_TO, 'DD/MM/RRRR') - (TO_DATE(', Select the record if the doc_status is 'R' and Date1 > Date2, Select the record if the doc_status is 'A'. [,default] ) the parameters of the oracle decode function are: - expression (mandatory):. A default value should also be specified to handle the 'unhandled' cases: SQL> select DECODE (SIGN (TO_DATE ('&pdate', 'DD/MM/RRRR') - (TO_DATE('10/02/2014','DD/MM/RRRR'))), 1, 'A', 'X') from dual; Ideally all three conditions should be explicitly handled with the default covering the unfortunate event when none of the expected values are returned: SQL> select DECODE (SIGN (TO_DATE ('&pdate', 'DD/MM/RRRR') - (TO_DATE('10/02/2014','DD/MM/RRRR'))), 1, 'A', 0, 'B', -1, 'X', 'Z') from dual; Even using dates in the BC range won't return 'Z': SQL> select DECODE (SIGN (TO_DATE ('&pdate', 'DD/MM/SYYYY') - (TO_DATE('10/02/2014','DD/MM/RRRR'))), 1, 'A', 0, 'B', -1, 'X', 'Z') from dual. Copyright 2011-2021 www.javatpoint.com. That function will return date2 if date2 <= date1. SQL Most of these functions return values that are accurate to 38 decimal digits. An old question, but since it got pulled out of obscurity by another answer, here is how I would try to replicate the decode function in C#. Plugging in the values and translating to pseudo-code, you get if 0 - 0 = 0 then date2 else date1 where both dates are the same. We can compare a basic DECODE function with a CASE function by taking a basic query as an example: In this query, 1 + 0 is our expression, 1,2,3 are the search values and 'One', 'Two' and 'Three' are results. DECODE. I think a much better example of how to use DECODE would be to show something like this to give an example of how the integer values represent strings that make sense in context. SQL> NVL2 They don't need to be in any specific order. Hi All- I have a requirement where i need to convert a case statement into a nested decode statement here is the scenario. I have a doubt here, my boolean fuction is in a package. After the execution of above code at SQL prompt, it produces the following result. expression_id - is an expression for comparison. Example of Oracle decode Given below is the example of Oracle decode: Code: SELECT DECODE (2, 2, 'Two') FROM dual; Explanation: This is a very simple example of decode function, in which the Oracle decode function compares the first search argument value with the second search argument value. To achieve this we will give the following command. select instr ('mohammed sami','a') from dual; The Oracle decode and case functions are used within the Oracle database to transform data values for one value to another. Accepts a 2-digit year and returns a 4-digit year. The following is the syntax of the Oracle Decode () function: DECODE (expression , search , result [, search , result] [, default (optional)]) Click Here - Get Prepared for SQL Interviews WWV_FLOW_CRYPTO.UNSUPPORTED_FUNCTION: The token is signed using an unsupported function. If the value is not found, the function will return NULL. Please mail your requirement at [emailprotected] Duration: 1 week to 2 week. Should I exit and re-enter EU with my EU passport or is it ok? is removing empty spaces before and after of. Example #1. In a previous post, Tom has shown that both DECODE and CASE will use short-circuit logic (as opposed to NVL and NVL2): The number functions available in Oracle are: ABS ACOS ASIN ATAN ATAN2 BITAND CEIL COS COSH EXP FLOOR LN LOG. Output: Addition is: 33 Statement processed. Michael is correct, that does not belong in a WHERE clause. The SIGN function returns one of three values: 1,0,-1. Some SQL dialects, including Db2, H2, Oracle know a more succinct, but maybe less readable DECODE () function with a variable number of arguments. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Example: In this example we will try to find the current date of the session using this function. This function decodes a raw token value. Syntax: SYSDATE For example, it will replace the 1st character in the string_to_replace with the 1st character in the replacement_string. I need to compare two dates using the Oracle decode function to see if one is less than or equal to the other. We need to specify the value that should be returned. Not the answer you're looking for? Package A (Function xyz ( ) return boolean is ( ..) Function xyz ( ) return number is ( ..)) Amending what I said earlier, having this in the WHERE clause is not a problem. This is an example of using Oracle DECODE in a WHERE clause. The Basics: What it is, and How it works. SELECT NVL2 ( NULL, 1, 2) -- 2 FROM dual; Code language: SQL (Structured Query Language) (sql) Can several CRTs be wired in parallel to one oscilloscope circuit? http://www.techonthenet.com/oracle/functions/sign.php, sign(a) returns -1 if a < 0, 0 if a = 0 and 1 if a > 0. 2.The Oracle as well as Oracle case statement will give us the transformation of values in following format. After all, 0 is a value which you want to treat as a different value, while NULL semantically makes more sense for specifying 'no filter'. Developed by JavaTpoint. A better solution, if you're using 8i or later is to use case: Since case allows inequality operators, it's much more readable. His example brings back 72,487 rows which would require the DECODE / CASE portion of the statement to be executed at least this many times - correct? the syntax of the decode function is: decode ( expression, search, result [, search, result]. Connect and share knowledge within a single location that is structured and easy to search. Creating Local Server From Public Address Professional Gaming Can Build Career CSS Properties You Should Know The Psychology Price How Design for Printing Key Expect Future. we can read the decode statement as if-else if statement. The basic syntax for writing DECODE function in SQL is as follows: DECODE (expression , search_1, result_1[, search_2, result_2].,[,search_n,result_n] [, default]); The parameters used in the above mentioned syntax are: expression: expression argument is the value which is to be searched and compared with. Regardless, don't forget to cut off the minutes when you're comparing dates, unless you want the comparison to the maximum precision. But given the use case, making the parameter NULL would be a little better. The function then returns the string '1' since they were found equal. DECODE(status, 1, "Pending", 2, "Updated", 3, "Processed", 4, "Canceled", "Open"); Yes, that's a great suggestion. The Pivot clause converts rows into columns using the aggregate function. If the character occurs in the string then returns the first position of its occurrence otherwise returns 0. Excellent point, I accounted for that already as I work with dates quite often but it's a good one to mention if others end up looking at this. Like I said, the syntax here might be wrong since no database is accessible for me right now to test run my sql. In this example, the first paramater is greater than the second so it will return 1.