SQL Query Part 2

Query 1.      Case stmt example

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 Tables                           Query                                               Result

EMP_JB		SELECT id	ANSWER
		,job	===============
ID JOB		,CASE	ID  JOB		STATUS
		WHEN  job  =  'Sales'
10 Sales		THEN  'Fire'	10	Sales	Fire
20 Clerk		ELSE  'Demote'	20	Clerk	Demote
		END  AS  STATUS
		FROM emp_jb;

Query 2. Fetch  first  "n"  rowsexample

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 Tables                           Query                                               Result

EMP_NM			SELECT	*	ANSWER
			FROM	emp_nm	=========
ID NAME			ORDER  BY  id  DESC		ID  NAME
			FETCH  FIRST  2  ROWS  ONLY;
10 Sanders					50	Hanes
20 Pernal					20	Pernal
50 Hanes

SQL Query Part 1

Query 1.      Join example

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 Tables                           Query                           Result

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Table 1                 Table 2 

EMP_NM			EMP_JB			SELECT	nm.id	ANSWER
							,nm.name	================
ID NAME			ID JOB				,jb.job	ID  NAME		JOB
						FROM	emp_nm  nm
10 Sanders			10 Sales				,emp_jb  jb	10	Sanders	Sales
20 Pernal			20 Clerk			WHERE	nm.id  =  jb.id	20	Pernal	Clerk
50 Hanes						ORDER  BY  1;

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Query 2.    Leftouterjoin  example

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 Tables                           Query                           Result

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Table 1                 Table 2 

EMP_NM			EMP_JB			SELECT	nm.id	ANSWER
							,nm.name	================
ID NAME			ID JOB				,jb.job	ID  NAME		JOB
						FROM	emp_nm  nm
10 Sanders			10 Sales			LEFT  OUTER  JOIN		10	Sanders	Sales
20 Pernal			20 Clerk				emp_jb  jb	20	Pernal	Clerk
50 Hanes						ON	nm.id  =  jb.id	50	Hanes
						ORDER  BY  nm.id;