How to Use Oracle SQL DECODE, CASE and PIVOT The original SQL language focused on providing standard selection, projection, and sorting of data. Making statements based on opinion; back them up with references or personal experience. (function() { That is why SQL (in general) requires that all expressions in an aggregation query need to be aggregation functions, except for columns mentioned in the group by. For more information on how we collect and use this information, please review our Privacy Policy. While d3code and case can be used interchangeably, the decode is more powerful because decode can change SQL results. Why is there an extra peak in the Lomb-Scargle periodogram? While we recommend that you use the CASE expression rather than the DECODE function, where feasible we provide both DECODE and CASE versions of each example to help illustrate the differences between the two approaches. Then how will you know if a porposed solution works or not? true, DECODE returns 'HEAD HONCHO' (the third If there is only a single row for each element name and you are trying to pivot rows to columns then you can use: SELECT MAX ( CASE WHEN pett.element_name = 'Basic Salary' THEN peevf.screen_entry_value ELSE 0 END ) AS Salary, MAX ( CASE WHEN pett.element_name = 'Transportation Allowance' THEN peevf.screen_entry_value ELSE 0 END ) AS . The equivalent logic using DECODE Explain, using specific examples, how you get those results from that data. Most of Oracle's built-in functions are designed to I have corrected them now, there was this extra comma after the last column. I assume this occurs because, as the names suggest, DECODE is a function and CASE isn't, which implies they have been implemented differently internally. than $2000: In this example, the and See my notes on the decode function. NULLIF function compares two 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. DECODE, The purpose of the Oracle DECODE function is to perform an IF-THEN-ELSE function. We do not currently allow content pasted from ChatGPT on Stack Overflow; read our policy here. It's similar to a CASE statement, but CASE is a statement where DECODE is a function. Do you even need recon_acc at all in this problem? Enhancements over the years allow SQL to deliver much more robust analysis of data. /* * * DON'T EDIT BELOW THIS LINE * * */ expression to see whether it is NULL. Please enable JavaScript to view the comments powered by Disqus. Really finding it tough to figure this out. if . nvl function always accepts two parameters. checking whether an employee's One of the readers of the blog has sent me a question regarding how to use the DECODE function in SQL Server. The same exception would We can say it is an extended version of Decode. Case was introduced in Oracle 8.1. Ready to optimize your JavaScript with Rust? NVL2 functions allow you to test an Decode Decode Function is used to compare values in the decode function and returns the result that match with comparison value. Add a new light switch in line with another switch? Zorn's lemma: old friend or historical relic? NULLIF, Can't you apply the same techniques to 'A0031'? status column to each of five values, and, if a Enhancements over the years allow SQL to deliver much more robust analysis of data. SET DEFINE OFF;Insert into RECON_ACC (ACC_ID, PARTION_ID) Values ('A0030',1);Insert into RECON_ACC (ACC_ID, PARTION_ID) Values ('A0031',2);COMMIT;/CREATE TABLE RECON_ACC( ACC_ID VARCHAR2(50), PARTITION_ID INTEGER)/CREATE TABLE abc.def( ACC_ID VARCHAR2(50), EFFECTIVE_DATE DATE, UPDATE_DATE DATE,)/CREATE TABLE abc100.def( ACC_ID VARCHAR2(50), EFFECTIVE_DATE DATE, UPDATE_DATE DATE,)/SET DEFINE OFF;Insert into abc.def (EFFECTIVE_DATE, UPDATE_DATE, ACC_ID) Values (TO_DATE('11/01/2013 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), TO_DATE('12/17/2013 13:58:31', 'MM/DD/YYYY HH24:MI:SS'), 'A0030');Insert into abc.def (EFFECTIVE_DATE, UPDATE_DATE, ACC_ID) Values (TO_DATE('11/01/2013 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), TO_DATE('11/19/2013 17:36:45', 'MM/DD/YYYY HH24:MI:SS'), 'A0030');Insert into abc.def (EFFECTIVE_DATE, UPDATE_DATE, ACC_ID) Values (TO_DATE('11/02/2013 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), TO_DATE('12/17/2013 13:58:38', 'MM/DD/YYYY HH24:MI:SS'), 'A0030');Insert into abc.def (EFFECTIVE_DATE, UPDATE_DATE, ACC_ID) Values (TO_DATE('11/03/2013 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), TO_DATE('12/17/2013 13:58:44', 'MM/DD/YYYY HH24:MI:SS'), 'A0030');Insert into abc100.def (EFFECTIVE_DATE, UPDATE_DATE, ACC_ID) Values (TO_DATE('11/01/2013 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), TO_DATE('12/12/2013 15:58:33', 'MM/DD/YYYY HH24:MI:SS'), 'A0031');Insert into abc100.def (EFFECTIVE_DATE, UPDATE_DATE, ACC_ID) Values (TO_DATE('11/01/2013 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), TO_DATE('11/19/2013 17:36:51', 'MM/DD/YYYY HH24:MI:SS'), 'A0031');Insert into abc100.def (EFFECTIVE_DATE, UPDATE_DATE, ACC_ID) Values (TO_DATE('11/02/2013 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), TO_DATE('11/29/2013 09:15:17', 'MM/DD/YYYY HH24:MI:SS'), 'A0031');Insert into abc100.def (EFFECTIVE_DATE, UPDATE_DATE, ACC_ID) Values (TO_DATE('11/03/2013 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), TO_DATE('11/29/2013 09:22:23', 'MM/DD/YYYY HH24:MI:SS'), 'A0031');COMMIT;/. Case And Decode Function In Oracle SQL (IF THEN ELSE) With Examples | CASE DECODE FUNCTIONS IN ORACLE SQLAbout this Video!------------------------------------------Hi Guys! The searched CASE statement evaluates multiple Boolean expressions and chooses the first one whose value is TRUE . How do I UPDATE from a SELECT in SQL Server? The DECODE function The following would work: SELECT DECODE (MAX (FLAG), 1, SUM (Qty2), SUM (Qty1)) FROM test_v WHERE item_no = 1234567; Note: I'm using decode () only because it is in your sample query. The NULLIF function compares this value Find centralized, trusted content and collaborate around the technologies you use most. and based on data values within a SQL statement without resorting to a The Oracle DECODE () function allows you to add the procedural if-then-else logic to the query. Unfortunately, your DECODE statement does not seem to match the requirements. But Employee.title = 'assistant' As I understand how decode functions, what you seem to required is: Unfortunately, your DECODE statement does not seem to match the requirements. The next example the maximum allowable parameters, which is 255. SQL | Using the 'Decode' and 'Case' statements in queries. NVL The intent is to determine whether each employee has a manager by third expression. Find all tables containing column with specified name - MS SQL Server. Case is a statement in Oracle. rev2022.12.11.43106. Is it correct to say "The glue on the back of the sticker is dying down so I can not stick the sticker to the wall"? If column1 is anything other than Lab, then your query would return NULL. Standard SQL alternative to Oracle DECODE A CASE expression is the ANSI SQL method, of which there are 2 varieties, "simple" and "searched": 1) Simple CASE expression: CASE col WHEN 1 THEN 'One' WHEN 2 THEN 'Two' ELSE 'More' END 2) Searched CASE expression: CASE WHEN col < 0 THEN 'Negative' WHEN col = 0 THEN 'Zero' ELSE 'Positive' END If Employee.title = 'assistant' --> THEN get the first non null value between Employee.title and 'NULL'. Does aliquot matter for final concentration? Oracle APEX in the Cloud / Managed Hosting, Free Oracle Database Administration Tutorials, Free Solaris 11, Oracle VM and ZFS Tutorials, Private: Free Oracle Database Administration Tutorials, How to Pivot (Flip) Tables with SQL CASE & DECODE, Advanced Oracle SQL Tutorial: case, decode, pivot. And by 'native', I am referring to the Oracle 'flavour' of SQL. match is found, returns the corresponding string. Because they are equal, the function returns the third argument which is the string 'One': SELECT DECODE ( 1, 1, 'One' ) FROM dual; })(); Null value functions in SQL 1) nvl It is oracle predefined function which is used to substitute or replace user defined value in place of null. var disqus_identifier = "webinar_137"; 2. . Is it possible to hide or delete the new Toolbar in 13.1? Since the DECODE function compares two expressions and returns one of column's value, as demonstrated by the next query, Thanks for contributing an answer to Stack Overflow! How is it that you can predict what the results for 'A0030' should be? The Wonder if it is possible using SQL or a cursor may be required. You might want to do something else, bind variables maybe. more complex logic: This example compares the value of a part's The DECODE function ensures that the divisor is something other than zero. [,default] ) The. If you need to find the last day of the Question 2:- Syntax of Case Statement CASE [expression] WHEN condition_1 THEN result_1 WHEN condition_2 THEN result_2 A CASE expression is the ANSI SQL method, of which there are 2 varieties, "simple" and "searched": 1) Simple CASE expression: CASE col WHEN 1 THEN 'One' WHEN 2 THEN 'Two' ELSE 'More' END. The . I'm just guessing at the join conditions between recon_acc and the other tables. You need to join both def tables in the query. types are identical or that they can at least be translated to be the two expressions to the caller, it is important that the expression Add a column with a default value to an existing table in SQL Server, How to check if a column exists in a SQL Server table, How to concatenate text from multiple rows into a single text string in SQL Server, LEFT JOIN vs. LEFT OUTER JOIN in SQL Server. Copyright eTutorials.org 2008-2021. ANSI Compatible: CASE is an ANSI standard. Irreducible representations of a product of two groups, Counterexamples to differentiation under integral sign, revisited. This webinar investigates how CASE, DECODE, PIVOT, and UNPIVOT provide these capabilities. example: Since the manager_emp_id column, which is numeric, FROM LettersTable. . DECODE GREATEST, LEAST , CASE . 'NONE' when no manager has been assigned (i.e., in this example compares each row's values to be returned for the case when an expression is NULL, and Standard SQL alternative to Oracle DECODE. are the same. SELECT REPLACE('oracleclub','oracle','db') name FROM DUAL; NAME-----dbclub . As per my knowledge, CASE is a statement and DECODE is a function which was defined in the Standard package. Location: DECODE is used only inside SQL statement. Dual EU/US Citizen entered EU on US Passport. It works similar to an IF statement within other languages. Don't forget to post your Oracle version, and an explanation of the results. You would only need a simple join, like this: The only problem here is that you have 2 separate def tables. comparable types. the comparison and must throw an exception. This webinar investigates how CASE, DECODE, PIVOT, and UNPIVOT provide these capabilities. If this were not the case, Oracle would If status = 'D' : 'Denied' 2. seems to me to return always 'assistant'. These functions are used to make decisions if-then-else statements. expresssion is NULL, presumably because the intent is clearer. CASE can do . Answer: The difference between decode and case are straightforward. If Syntax Why don't you want any results from 'A0031'? CASE DECODE . You can use a CASE expression in any statement or clause that accepts a valid expression. Help us identify new roles for community members, Proposing a Community-Specific Closure Reason for non-English content. In this video, we shall see how case and decode is used in real time scenario. The original SQL language focused on providing standard selection, projection, and sorting of data. Examples of frauds discovered because someone tried to mimic a random sequence. the first expression otherwise. Substitute your real names when you run this. produce the same results as the DECODE example shown in a previous var disqus_shortname = "skillbuilders"; // required: replace example with your forum shortname First thing is why do you want to use case inside decode. GREATEST function is just the ticket. demonstrates how additional sets of parameters may be utilized for found, then the string 'Unknown' is returned. function to use. If we use DECODE, the package has to load first, so it will take a little longer than the CASE. How to get the identity of an inserted row? We can use the CASE in the where clause and can not use the DECODE in the where clause. Why do some airports shuffle connecting passengers through security again, Disconnect vertical tab connector from PCB, Arbitrary shape cut into triangles and packed into rectangle of the same area. specialized versions of DECODE. But your original script from a logic point of view does not seems completely correct. CASE EXPRESSION2. 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First, a case statement needs an end CASE WHEN column1 = 'Lab' THEN DECODE ( column2, 'Reg1', 'Zone1', 'Reg2', 'Zone2', 'DefaultZone') END CollectionZone I would strongly suspect, though, that you're missing an ELSE in your CASE. Let's look at a simple example using If you'd like help, post a little sample data (CREATE TABLE and INSERT statements, relevant columns only) for all tables involved, and also post the results you want from that data. be thrown if the two return expressions (E3 and E4) did not have For example, you can use the CASE expression in statements such as SELECT, UPDATE, or DELETE, and in clauses like SELECT, WHERE, HAVING, and ORDDER BY. section: NVL2 looks at the first expression, manager_emp_id The Since the manager_emp_id column, which is numeric, cannot be converted to a DATE type, the Oracle server cannot perform the comparison and must throw an exception. You need to join both def tables in the query. If a match is not We can use CASE any where in SQL, even as a parameter of a function/procedure. NVL2 functions, however, do not solve a procedural language like PL/SQL. In SQL Server the equivalent code is CASE statement. Following is the list of differences -. The following sections present a variety of examples illustrating the uses of conditional logic in SQL statements. Here is the table structures and data I have got. the 4 parameters of the earlier example, we are still a long way from Topics Syntax Semantics Examples The CASE expression evaluates a list of conditions and returns one of the multiple possible results. Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. For information, in Oracle SQL the DECODE is a form of CASE as follows: If status = 'A' : 'Accepted' /* * * CONFIGURATION VARIABLES: EDIT BEFORE PASTING INTO YOUR WEBPAGE * * */ If the first expression is not NULL, NVL2 returns var disqus_title = "Advanced Use of Oracle DECODE CASE PIVOT UNPIVOT"; It allows you to provide a value, and then evaluate other values against it and show different results. The previous example demonstrates the use of a DECODE function with To subscribe to this RSS feed, copy and paste this URL into your RSS reader. If status = 'D' : 'Denied'. the syntax and logic equivalent for each of the four functions. SELECT CASE WHEN COL2 > 10 THEN 'YES', WHEN COL2 < 10 THEN 'NO' ELSE 'N/A' end FROM TEST_TABLE; If you insists in using decode and case then rearrange your query like this CASE is a simple statement which is ANSI standard. NULL, and the third and fourth expressions are character literals. Otherwise, the column value itself is most people prefer to use NVL or NVL2 when checking to see if an The explanation is always important; otherwise, you might get a solution that just happens to work for the sample data you post, but not for other data. Can several CRTs be wired in parallel to one oscilloscope circuit? also for the case when an expression is not NULL. There's no real way to prove this. Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production, For the results, if partition_id for the acc_id is 1 then use to fetch from abc.def table else if partition_id is 2 use abc100.def table, I want results from AA031 also, just that if I can figure out how to do A0030, i was assuming AA031 will be easy enough then. an expression is NULL, you can return an alternate, non-NULL value, What is the difference between decode and case - YouTube 0:00 / 10:59 What is the difference between decode and case 78,248 views Jul 29, 2018 1.1K Dislike Share Save Siva Academy 32.7K. raise an exception, as illustrated by the following Are you saying that you don't know what the results from 'A0031' (or is it 'AA031') should be? Would like to stay longer than 90 days. The next example shows the ID of each Here is the CASE version of the statement: SELECT p.part_nbr, SYSDATE + (p.inventory_qty / CASE WHEN my_pkg.get_daily_part_usage (p.part_nbr) > 0 THEN my_pkg.get_daily_part_usage (p.part_nbr) ELSE 1 END) anticipated_shortage_dt FROM part p WHERE p.inventory_qty > 0; Else : 'Other'. Although the 12 parameters in this example are a great deal more than How can I delete using INNER JOIN with SQL Server? A basic foundation in SQL is required. the second expression. DECODE: In this example, the first expression is a column, the second is same type. Since any of the expressions in a DECODE Else : 'Other'. SELECT lname, DECODE(manager_emp_id, SYSDATE, 'HEAD HONCHO', 'WORKER BEE') emp_type FROM employee; ERROR at line 1: ORA-00932: inconsistent datatypes: expected DATE got NUMBER. SQL> INSERT INTO emp . To learn more, see our tips on writing great answers. more expressions as arguments. 3. Why are you storing your data in a way that creates problems? 1. How were sailing warships maneuvered in battle -- who coordinated the actions of all the sailors? 2000, whichever is greater. DECODE (SUM (DECODE (a.canceldate, NULL, 1,0)), 1, NULL, To_Date (MAX (TO_CHAR (a.canceldate,'yyyymmdd')), 'yyyymmdd')) dCancelDate, As I inteprete is to convert it like: case a.canceldate (when sum (case a.canceldate when Null then 1 else 0 end)) when 1 then 0 else convert (datetime,a.canceldate) end max (a.canceldate) as dCancelDate, expression); otherwise, 'WORKER BEE' (the last which shows salary information for only those employees making less Should I exit and re-enter EU with my EU passport or is it ok? Would it be possible, given current technology, ten years, and an infinite amount of money, to construct a 7,000 foot (2200 meter) aircraft carrier? dsq.src = 'http://' + disqus_shortname + '.disqus.com/embed.js'; Note that DECODE and CASE behave differently when comparing NULL values: DECODE considers two NULLs to be "the same", which is an exception to the rule that comparing a NULL to anything has an "unknown" result. function returns either the employee's salary or SQL used in the video is given below.SELECT * FROM emp_test ORDER BY gender;c. in this case. Check: DECODE works on the basis of an equality check. I doubt that cursors or PL/SQL would be necessary, or even helpful, in ths problem. the minimum number of parameters (four). specific problem; rather, they are best described as inline In the following example, the Oracle DECODE () function compares the first argument (1) with the second argument (1). Convert Decode(case from oracle to sql server. . Each E3 and E4 have the same type. subquery. NULL (the second expression). Not the answer you're looking for? I started writing my previous reply before this message appeared. It is also perform transfer your data to the another data. 1. Case And Decode Function In Oracle SQL (IF THEN ELSE) With Examples | CASE DECODE FUNCTIONS IN ORACLE SQLAbout this Video!-----. We use cookies and browser activity to improve your experience, personalize content and ads, and analyze how our sites are used. NOTE: Some corporate firewalls will not allow videos hosted by YouTube. function Today we will learn Conditional Expressions in Oracle SQL Programming, there are two types of Conditional Expressions are as follows:1. Using UNION, you can create a result set that makes those 2 tables appear as 1; for example: I called the small def tables abc_def and abc100_def just so I wouldn't have to create new schemas. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. For information, in Oracle SQL the DECODE is a form of CASE as follows: select id, decode (status,'A','Accepted','D','Denied','Other') from contracts; Will return for each id: If status = 'A' : 'Accepted'. Connect and share knowledge within a single location that is structured and easy to search. manager_emp_id column is NULL. After a brief review, we will show how these features allow you to do range comparisons, create horizontal and vertical histograms, and flip tables on the side by converting rows into columns and columns into rows. Audience: Oracle and APEX developers who want to improve their SQL skills. The CASE statement chooses from a sequence of conditions and runs a corresponding statement. Why is Singapore currently considered to be a dictatorial regime and a multi-party democracy by different publications? to the employee's salary and returns NULL if they The DECODE Test (and, if necessary, correct) your CREATE TABLE and INSERT statements before you post them. Always say which version of Oracle you're using (e.g., 11.2.0.2.0). employee's manager, but substitutes the word Once again, this problem only occurs because you have 2 separate def tables. Hopefully, the next section will convince you to use CASE expressions can be thought of as an inline IF statement. See the forum FAQ: https://forums.oracle.com/message/9362002. Easier to Read: CASE is more flexible and easier to read than DECODE. cannot be converted to a DATE type, the Oracle server cannot perform The tutorial session you want to view requires your registering with us. Decode statement can be used with only SQL DML statements like SELECT, INSERT, UPDATE, DELETE. manager_emp_id column (the first expression) to Asking for help, clarification, or responding to other answers. you won't need to worry about which built-in The If that expression evaluates to NULL, NVL2 returns the var dsq = document.createElement('script'); dsq.type = 'text/javascript'; dsq.async = true; You can then use a DECODE (or CASE) expression to get data from one or the other. Are defenders behind an arrow slit attackable? Using Oracle's Data Type Summary, DECODE is returning a VARCHAR2 (data type 1) whereas the CASE statements are "returning" numbers (data type 2). expression) is returned. 2) Searched CASE expression: Here is the results I would obtain for A0031: Software in Silicon (Sample Code & Resources), https://forums.oracle.com/message/9362002. solve a specific problem. ST_Tesselate on PolyhedralSurface is invalid : Polygon 0 is invalid: points don't lie in the same plane (and Is_Planar() only applies to polygons). statement can be NULL, the NVL and NVL2 functions are actually when a column is NULL. The DECODE function in Oracle allows you to have IF-THEN-ELSE logic in your SQL statements. But DECODE is internal to Oracle. I added the sub-query date_range as a way of passing the date parameters. DECODE takes three or We start with two functions that perform a similar task: setting the value of a field based on a set of pre-defined conditions. DECODE can work with only scaler values but CASE can work with logical oprators, predicates and searchable subqueries. You can then use a DECODE (or CASE) expression to get data from one or the other. This is a multi-part tutorial. SELECT DISTINCT E.ACC_ID, P.EFFECTIVE_DATE, P.UPDATE_DATE FROM (choose abc.def table in case RECON_ACC.partition_id is 1 for that acc_id abc100.def table in case RECON_ACC.partition_id is 2 for that acc_id ) p INNER JOIN (select * from RECON_ACC where partition_id is NOT NULL) e ON P.ACC_ID = E.ACC_ID AND TRUNC (P.UPDATE_DATE) >= '31-DEC-13' AND TRUNC (P.UPDATE_DATE) <= '02-JAN-14'; Can anyone help me to do a SQL query to achieve this? The simple CASE statement evaluates a single expression and compares it to several potential values. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Then whenever you are in need of if-then-else functionality. 5.5 Subquery Case Study: The Top N Performers, 6.4 Getting Temporal Data In and Out of a Database, 7.5 Rules and Restrictions on Set Operations, 8.1 Representing Hierarchical Information, 11.3 Calling Stored Functions from Queries, 11.4 Restrictions on Calling PL/SQL from SQL, 13.3 The GROUPING_ID and GROUP_ID Functions, 15.1 Know When to Use Specific Constructs, 15.3 Consider Literal SQL for Decision-Support Systems, 17.1 Elementary Regular Expression Syntax. If the result of the comparison is Then make sure the code you post works, too. While the decode operator has been around since the earliest days of Oracle, the case operator was introduced in Oracle 8.1.6. looks as follows: NULLIF is useful if you want to substitute NULL for a expressions and returns NULL if the expressions are equivalent, or Is there any reason why you can't jsut use 1 unified_def table? Don't forget to post your Oracle version, the restults you want from the given sample data, and an explanation of how you get those results from that data. These features are particularly useful to identify trends in data. And best of all, once you are registered, youll also have access to all the other 100s of FREE Video Tutorials we offer! Is that really what you want? The version might not be significant in this case, but it's so easy to post that you might as well do it. month containing a particular date, for example, the LAST_DAY Here are the results that I would need for A0030 from ABC.DEF. returned. Simplify it using only CASE. CASE can work as a PL/SQL construct but DECODE is used only in SQL statement.CASE can be used as parameter of a function/procedure. The following example uses NVL2 to If you only had one def table, then this would be easy. This example works because E1 can be compared to E2, and Table 9-1 shows DECODE result type is first decoded expression type, all others are implicitly converted (if needed). It is same as decode for perform IF-THEN-ELSE logic. All rights reserved. When people post solutions, would you like them to work? SELECT DECODE (Letters, 'First',1, 'Second',2, 'Third',3, 0) AS LN. There are errors in 2 of the CREATE TABLE statements, and the column names in the CREATE TABLE statements don't always match the names in the INSERT statements. NVL, (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(dsq); How can I do an UPDATE statement with JOIN in SQL Server? If you'd like help, post a little sample data (CREATE TABLE and INSERT statements, relevant columns only) for all tables involved, and also post the results you want from that data. All these SQL examples assume you are working on an Oracle database. with data (a, b) as ( select 1,1 from dual union all select 1,null from dual union all select null,1 from dual union all Hello I have this part of a script in oracle and I need to move it in Microsfot Sql Server: Can someone please help me tell how it's correct? Use NVL2 when you wish to specify alternate 2.The Oracle as well as Oracle case statement will give us the transformation of values in following format. expression can be a column, a literal, a function, or even a The syntax is: 1 1 DECODE ( expression, search, result [, search, result]. when manager_emp_id is NULL): Even though DECODE may be substituted for any NVL or NVL2 function, Lessons 1 through 3 are available now. The NVL function is most commonly used to substitute a default value to use in its place. 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