How do you write a nested case statement in Teradata?

How do you write a nested case statement in Teradata?

Nested Case statement in Teradata

  1. SELECT EmpID,
  2. CASE.
  3. WHEN Emp_Type=’Employee’ THEN.
  4. CASE EmpDesignation.
  5. WHEN ‘Software Engineer’ THEN 25000+500.
  6. WHEN ‘Senior Engineer’ THEN 35000+1000.
  7. WHEN ‘Team manager’ THEN 50000+2000.
  8. END.

Can we use CASE statement in where clause Teradata?

This check should happen in the where clause . To expand on the excellent answer, you can’t combine case and where in . You’d have to use dynamic sql for that, which macros don’t support, I don’t think. So you have to use this or logic.

How to insert data from one table to another in teradata?

Syntax: To insert all the records in all the columns. To insert records in fewer columns….INSERT/SELECT in Teradata

  1. INSERT INTO table2.
  2. SELECT (column1, column2, column3) FROM table1;
  3. or.
  4. INSERT INTO table2 (columna, column b, column c)
  5. SELECT (column1, column2, column3) FROM table1;

Can we use subquery in case statement in Teradata?

Teradata supports Scalar Subqueries only in some special cases within WHERE/HAVING. You’ll have to rewrite it to (Outer) Joins.

How do you use case and coalesce in SQL?

The SQL COALESCE function can be syntactically represented using the CASE expression. For example, as we know, the Coalesce function returns the first non-NULL values. SELECT COALESCE (expression1, expression2, expression3) FROM TABLENAME; The above Coalesce SQL statement can be rewritten using the CASE statement.

What is coalesce in Teradata?

Teradata COALESCE is used for NULL handling. The COALESCE is a statement that returns the first non-null value of the expression. It returns NULL if all the arguments of the expression evaluate to NULL.

How do you insert all records from one table that do not exist in another table?

  1. Insert Where Not Exists. SQL. Transact-SQL. INSERT INTO #table1 (Id, guidd, TimeAdded, ExtraData) SELECT Id, guidd, TimeAdded, ExtraData FROM #table2 WHERE NOT EXISTS (Select Id, guidd From #table1 WHERE #table1.id = #table2.id)
  2. Merge. SQL. Transact-SQL.
  3. Insert Except. SQL. Transact-SQL.
  4. Left Join.

How do I copy a table in Teradata?

COPY TABLE STRUCTURE and DATA in Teradata

  1. CREATE TABLE database. tablename_now AS database. tablename_previous.
  2. WITH NO DATA;
  3. INSERT INTO database. tablename_now SELECT * FROM database. tablename_previous.

Can we use subquery in case?

A subquery in the ELSE clause works the same way as a subquery in the THEN clause. We use a passthru predicate to evaluate the subquery conditionally. Similarly, a CASE expression with multiple WHEN clauses with subqueries in each THEN clause also works the same way.

Can we write select query in case statement?

The case statement in SQL returns a value on a specified condition. We can use a Case statement in select queries along with Where, Order By, and Group By clause. It can be used in the Insert statement as well.

Can we use case inside COALESCE?

Can you COALESCE in a CASE statement?

In the example, the CASE statement can be replaced with SELECT COALESCE(C1, 0) that produces the same output.

What is CASE statement in Teradata?

Teradata’s CASE statement is used to check for various conditions and in a sequential manner to produce the clustering results based on which conditional is met first.

What is Nullif in Teradata?

COALESCE function in Teradata returns NULL if all arguments evaluate to null; otherwise it returns the value of the first non-null argument. NULLIF is to used evaluate two expressions and returns NULL if the two arguments are equal otherwise if returns the first arguments.

How do you insert data if not exists SQL?

INSERT NOT EXISTS Syntax

  1. INSERT INTO your_table_name (column1, column2..)
  2. SELECT * FROM (SELECT value1, value2,….) AS temp.
  3. WHERE NOT EXISTS ();

Which SQL statement is used to insert a new data in a database?

The INSERT INTO statement
The INSERT INTO statement is used to insert new records in a table.

How do I create a query table in Teradata?

Teradata – Create Tables

  1. Table Options − Specifies the physical attributes of the table such as Journal and Fallback.
  2. Column Definition − Specifies the list of columns, data types and their attributes.
  3. Index Definition − Additional indexing options such as Primary Index, Secondary Index and Partitioned Primary Index.

How do I create a selection table in Teradata?

CREATE TABLE active_employees AS ( SELECT * FROM employee e WHERE e.active_flg = ‘Y’ ) WITH DATA;

  1. Create a full copy of an existing table.
  2. Create a new copy of a table that contains only some of the original records – a subset.
  3. Create an empty table but with exactly the same structure of the original.

Can case return multiple values SQL?

@yzhang – With CASE only the first match will return values. If you want the possibility of multiple conditions mathcing each input row, you need to make each check indpendantly, and UNION the results together.

How do you write a multiple case statement in SQL?

Here are 3 different ways to apply a case statement using SQL:

  1. (1) For a single condition: CASE WHEN condition_1 THEN result_1 ELSE result_2 END AS new_field_name.
  2. (2) For multiple conditions using AND: CASE WHEN condition_1 AND condition_2 THEN result_1 ELSE result_2 END AS new_field_name.

How to execute 2 SQL statements inside a case?

If employee statecode is AR,then update to FL

  • If employee statecode is GE,then update to AL
  • For all other statecodes update value to IN
  • Where does case statement go in SQL?

    – The CASE statement always goes in the SELECT clause – CASE must include the following components: WHEN, THEN, and END. ELSE is an optional component. – You can make any conditional statement using any conditional operator (like WHERE ) between WHEN and THEN. This includes stringing together multiple conditional statements using AND and OR. – You can include multiple WHEN statements, as well as an ELSE statement to deal with any unaddressed conditions.

    How to generate automatic number in Teradata SQL?

    – Specifying set_table=True also requires specifying primary_index or timecode_column. – Creating SET table (set_table=True) may result in loss of duplicate rows. – This argument has no effect if the table already exists and if_exists=’append’.

    How to use a case statement in a SQL query?

    expression (optional): This is the expression that the CASE statement looks for.

  • condtion_1/condition_n (mandatory): These values are a result of the expression parameter mentioned.
  • result_1/result_n (mandatory): These values are the value to display if the related condition is matched.