coalesce teradata

,comm,-1)-------------------- ------------------SMITH-1ALLEN 300WARD 500JONES-1MARTIN 1400BLAKE-1CLARK-1SCOTT-1KING-1TURNER 0ADAMS-1JAMES-1FORD-1MILLER-1Rows selected. 3. Nullif functionNullif (EXPR1,EXPR2)Returns null (NULL) if EXPR1 and expr2 are equal, or returns EXPR1. --show that those who have changed jobs are working, working, not changing jobs, and showing null.Sql> Col last_name for A15Sql> Select E.last_name, E.job_id,j.job_id,nullif (e.job_id, j.job_id) "Old Job ID"2 from Employees E

Coalesce is actually a useful function in SQL, and coalesce () is the primary function of returning the first non-null value;For example:COALESCE (NULL, NULL, 2, 4) ==> returns 2,COALESCE (null,null) ==> returns nullOf course, the primary function of the COALESCE () function determines whether a value is null, and if s

OracleDBNVL, NVL2, NULLIF, COALESCE Functions Oracle db nvl, NVL2, NULLIF, COALESCE Functions Regular Functions The following functions are applicable to any data type and use null values: • NVL (expr1, expr2) • NVL2 (expr1, expr2, expr3) • NULLIF (expr1, expr2) • COALESCE (expr1, expr2,..., exprn) The following functions are applicable to any data typ

SQL ISNULL (), NVL (), ifnull () and coalesce () functions, which are often used in our SQL statements, let's take a look at the example tutorial. p_id ProductName UnitPrice UnitsInStock UnitsOnOrder1 Jarlsberg 10.45 16 152 Mascarpone 32.56 233 Gorgonzola 15.67 9 20 Suppose that the "UnitsOnOrder" column is optional and may contain null values. We have the following SELECT statement: Select productname,unitprice* (unitsinstock+unitsonorder) from

PLSQL _ basic series 6_determine the operation NVL/NULLIF/COALESCE/NVL2, plsqlnvl BaoXinjian I. Summary The following functions are applicable to any data type and use null values:NVL (expr1, expr2)NVL2 (expr1, expr2, expr3)NULLIF (expr1, expr2)COALESCE (expr1, expr2,..., exprn) Ii. Case study-NVL 1. The NVL function format is as follows: NVL (expr1, expr2) 2. Meaning: if the first oracle parameter is b

Syntax: coalesce (T V1, t V2 ,...)The first non-null value in the returned parameter. If all values are null, null is returned. Take the EMP table as an example: desc emp;empno int None ename string None job string None mgr int None hiredate

2014-12-08 BaoxinjianI. Summary The following functions are available for any data type and are suitable for use with null values:NVL (EXPR1, EXPR2)NVL2 (Expr1, EXPR2, EXPR3)Nullif (EXPR1, EXPR2)COALESCE (EXPR1, expr2, ..., exprn)Second, case-NVL 1. The format of the NVL function is as follows: NVL (EXPR1,EXPR2)2. The meaning is: if the first parameter of Oracle is empty then the value of the second parameter is displayed, and if the value

http://blog.csdn.net/baoshan/article/details/2907602 COALESCE () Usage Select COALESCE (null,null, ' 1 ', ' 2 ') returns 1 Action returns the first NON-EMPTY expression in its argument. IsNull () Usage Select isnull (null,0) returns 0 Action encountered null return specified value Nullif () Usage nullif (' AA ', ' AA ') returns NULL, NULLIF (1,2) returns 1 Action two values equal returns null http://blo

Tags: ar c sql table har string BS return simpleThere must be a case in SQL Server where the values of a column in a table are stitched together into strings, "," or other symbols, which we would normally do:declare @returnValue nvarchar (max) = ";Select @returnValue + = ', ' +col1 from Table1 where ....Set @returnValue =substring (@returnValue, 1,len (@returnValue)-1)--Remove the front,Then the value of the @returnvalue variable is intercepted, so the operation actually feels very cumbersome to

Tags: ora1.NVL (EXP1,EXP2)NVLlets you replace null (returned as a blank) with a string in the results of a query. Ifexpr1is null and thenNVLreturnsexpr2. Ifexpr1is isn't null, thenNVLreturnsexpr1.The function is to handle null values in an expression: Assuming that the expression EXP1 is null, the function returns the value of the expression Exp2, Assuming that the expression EXP1 is not a null value, the function returns the value of the expression Exp1.2.NVL2 (EXP1,EXP2,EXP3)NVL2lets determine

Java code1. NVL FunctionThe NVL function format is as follows: NVL (expr1, expr2)If the first oracle parameter is null, the value of the second parameter is displayed. If the value of the first parameter is not empty, the original value of the first parameter is displayed.2. NVL2 FunctionsThe format of the NVL2 function is as follows: NVL2 (expr1, expr2, expr3)If the first parameter of the function is null, the value of the third parameter is displayed. If the value of the first parameter is not

Requirement: Splits a string that uses a delimiter connection for a fixed number of digits, such as splitting a record 215|482|850|870 into 215,482,850,870 four recordsResult: The WITH RECURSIVE statement is capable of implementing this function and

One-time modification of the closed source Entity Provider assembly to be compatible with the new EntityFramework process, assembly After reading this article, you will know how to directly modify a DLL without the source code to remove the strong naming restrictions on the DLL, add your "friend assembly" directly on the Assembly (a special Attribute that is applied to the Assembly so that the internal type in the Assembly can be directly called by other assembly) ". Similarly, you can use this

Mr. Huang took an SQL statement and asked me if I could optimize it. After reading it, the data volume is not large and the query is not complex. The record optimization process is as follows:DB: PostgreSQL 9.1OS: CentOS 6Count (d_personal_report_view )~ 9 K entries. The field type involved in the amount is numeric (9, 2 ).Original SQL: select distinct c.doctor_name,c.department_name,c.hospital_id,c.hospital_name,c.part_hospital_name,t.* from d_personal_report_view c,( select dc.part_hospi

The COALESCE () function can accept a series of values. If all items in the list are null, only one value is used. Then, it returns the first non-null value. This technique describes two ways to creatively use the COALESCE () function in SQLServer. Here is a simple example: there is a Persons data table, which has three fields FirstNam The COALESCE () function ca

Tags: SQL optimization Original Sqlselectcoalesce (SUM (Telecom_count), 0) AStelecom_count, coalesce (SUM (Telecom_money), 0) AStelecom_money, coalesce (SUM (Mobile_count), 0) ASmobile_count, coalesce (SUM (Mobile_money), 0) ASmobile_money, COALESCE (SUM (Unicom_count), 0) ASunicom_count,

Parallel Database for OLTP and OLAPJust ASurvey article on materials in parallel database products andTechnologies for OLTP/OLAP applications. It mainly covers majorCommercial/academic efforts on developing parallel DBMS to solve theEver growing large amount of relational data processing problem.Part I–parallel DBMSs1.1 Parallel Database for OLAP (SHARED-NOTHING/MPP)TeraData–teradata Home–

verification is a prerequisite to ensure the program runs well. Similarly, it is important to verify and process input parameters in DB2. Correct verification and preprocessing operations include: If the input parameter is incorrect, the stored procedure should return a clear value to inform the customer application. Then, the customer application can process the returned value or submit a new parameter to the stored procedure, or call other programs. Input parameters are pre-process

document (documents) consists of these: Post.title Post.content Author.name of Post All tag.name associated with the post Generate documents based on these requirements, which should be the case for SQL queries: SELECT Post.title | | ' ' || post.content | | ' ' || Author.name | | ' ' || COALESCE (String_agg (Tag.name, '), ') as document from Post JOIN author on author.id = post.author_id JOIN posts_tags On posts_ta

Label::) Off-Topic Long time no writing essays recently always for other things to worry about reverse telecommuting emotional problems and mood is low and so bad mood is not easy to get sick yesterday burned a day well all over the family is my all want to support me and bring me a large part of the pressure of the program Monkey Baby or a lot of improve themselves bar (old?????? ) Old Select t1.*, Case when coalesce (T2. score,0) = 0 Then 0 elseroun