QUESTION.1 WHAT IS
THE DIFFERENCE BETWEEN FASTLOAD AND MULTILOAD?
ANSWER: FASTLOAD USES
MULTIPLE SESSIONS TO QUICKLY LOAD LARGE AMOUNT OF DATA ON EMPTY TABLE.
MULTILOAD IS USED FOR HIGH-VOLUME MAINTENANCE ON TABLES AND VIEWS. IT WORKS
WITH NON-EMPTY TABLES ALSO. MAXIMUM 5 TABLES CAN BE USED IN MULTILOAD.
QUESTION.2 WHICH IS
FASTER?
ANSWER: FASTLOAD.
QUESTION.3 DIFFERENCE
BETWEEN INNER JOIN AND OUTER JOIN?
ANSWER: AN INNER JOIN
GETS DATA FROM BOTH TABLES WHERE THE SPECIFIED DATA EXISTS IN BOTH TABLES.
AN OUTER JOIN GETS DATA FROM THE SOURCE TABLE AT ALL TIMES,
AND RETURNS DATA FROM THE OUTER JOINED TABLE ONLY IF IT MATCHES THE CRITERIA.
QUESTION.4 WHAT IS
MULTI INSERT?
ANSWER: INSERTING
DATA RECORDS INTO THE TABLE USING MULTIPLE INSERT STATEMENTS. PUTTING A SEMI
COLON IN FRONT OF THE KEY WORD INSERT IN THE NEXT STATEMENT RATHER THAN
TERMINATING THE FIRST STATEMENT WITH A SEMI COLON ACHIEVES IT.
INSERT INTO SALES “SELECT * FROM CUSTOMER”
INSERT INTO LOAN “SELECT * FROM CUSTOMER”;
QUESTION.5 IS MULTI
INSERT ANSI STANDARD?
ANSWER: NO.
QUESTION.6 HOW DO YOU
CREATE A TABLE WITH AN EXISTING STRUCTURE OF ANOTHER TABLE WITH DATA AND WITH
NO DATA?
ANSWER: CREATE TABLE
CUSTOMER DUMMY AS CUSTOMER WITH DATA / WITH NO DATA;
QUESTION.7 WHAT IS
THE OPENING STEP IN BASIC TERADATA QUERY SCRIPT?
ANSWER: LOGON
TDIPID/USERNAME, PASSWORD.
QUESTION.8 YOU ARE
CALLING A BTEQ SCRIPT, WHICH DROPS A TABLE AND CREATES A TABLE. IT WILL THROW
AN ERROR IF THE TABLE DOES NOT EXIST. HOW CAN YOU DO IT WITHOUT THROWING THE
ERROR?
ANSWER: YOU CAN IT BY SETTING ERROR LEVEL TO ZERO BEFORE
DROPPING AND RESETTING THE ERROR LEVEL TO 8 AFTER DROPPING.
QUESTION.9 ERRORLEVEL
(3807)
ANSWER: SEVERITY 8;
QUESTION.10 CAN YOU
FASTEXPORT A FIELD, WHICH IS PRIMARY KEY BY PUTTING EQUALITY ON THAT KEY?
ANSWER: NO.
QUESTION.11 DID YOU
WRITE STORED PROCEDURES IN TERADATA?
ANSWER: NO, BECAUSE
THEY BECOME A SINGLE AMP OPERATION AND MY COMPANY DIDN’T ENCOURAGE THAT.
QUESTION.12 WHAT IS
THE USE OF HAVING INDEX’S ON TABLE?
ANSWER: FOR FASTER
RECORD SEARCH.
QUESTION.13 DID YOU
USE QUERY MAN OR SQL ASSISTANCE?
ANSWER: SQL ASSISTANT
6.1
QUESTION.14. I AM
UPDATING A TABLE IN BTEQ. IT HAS TO UPDATE A LARGE NUMBER OF ROWS, SO IT’S
REALLY SLOW. WHAT DO YOU SUGGEST?
ANSWER: IN TERADATA IT IS NOT RECOMMENDED TO UPDATE MORE
THAN 1 MILLION ROWS DUE TO JOURNAL SPACE PROBLEMS, IF IT IS LESS THAN THAT AND
IT’S SLOW IN THE BTEQ, YOU MIGHT WANT TO ADD COLLECT STATISTICS STATEMENT
BEFORE THE UPDATE STATEMENT.
QUESTION.15 IS IT
NECESSARY TO ADD? QUIT STATEMENT AFTER A BTEQ QUERY WHEN I AM CALLING IT IN A
UNIX ENVIRONMENT?
ANSWER: NOT NECESSARY
BUT IT IS GOOD TO ADD A QUIT STATEMENT AFTER A QUERY.
QUESTION.16 THERE IS
A COLUMN WITH DATE IN IT. IF I WANT TO GET JUST MONTH HOW IT CAN BE DONE? CAN I
USE SUB STRING?
ANSWER: SUB STRING IS
USED WITH CHAR FIELDS. SO IT CANNOT BE USED. TO EXTRACT MONTH FROM A DATE
COLUMN, EX SELECT EXTRACT (MONTH FROM ). SAME THING FOR YEAR OR DAY.OR HOUR OR
MINUTES IF IT’S A TIME STAMP (SELECT EXTRACT (MINUTE FROM COLUMN NAME).
QUESTION.17 WHAT’S
THE SYNTAX OF SUB STRING?
ANSWER: SUBSTRING
(STRING_EXPRESSION, N1 [N2])
QUESTION.18 DID YOU
USE CASE WHEN STATEMENT. CAN YOU TELL US A LITTLE ABOUT IT?
ANSWER: YES. WHEN A
CASE HAS TO BE SELECTED DEPENDING UPON THE VALUE OF THE EXPRESSION.
QUESTION.19 WHILE
CREATING TABLE MY DBA HAS FALLBACK OR NO FALLBACK IN HIS DDL. WHAT IS THAT?
ANSWER: FALLBACK
REQUESTS THAT A SECOND COPY OF EACH ROW INSERTED INTO A TABLE BE STORED ON
ANOTHER AMP IN THE SAME CLUSTER. THIS IS DONE WHEN AMP GOES DOWN OR DISK FAILS.
Question.
20 Highlight a few of the important components of Teradata.
Some of the important components of
Teradata are: –
- Bynet
- Access Module Processor (AMP)
- Parsing Engine (PE)
- Virtual Disk (vDisk)
- Virtual Storage System (VSS)
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