JDBC Faqs

JDBC Interview Faqs
# How do I check what table-like database objects (table, view, temporary table,

# How do I create a database connection?

# How do I create a java.sql.Date object?

# How do I create a java.sql.Time object?

# How do I create an updatable ResultSet?

# How do I disallow NULL values in a table?

# How do I display and parse a date?

# How do I execute stored procedures?

# How do I extract SQL table column type information?

# How do I extract a BLOB from a database?

# How do I extract the SQL statements required to move all tables and views from an existing database to another database?

# How do I find all database stored procedures in a database?

# How do I get runtime information about the JDBC Driver?

# How do I implement a RowSetReader? I want to populate a CachedRowSet myself and the documents specify that a RowSetReader should be used.The single method accepts a RowSetInternal caller and returns void. What can I do in the readData method?

# How do I insert a .jpg into a mySQL data base?

# How do I insert an image file (or other raw data) into a database?

# How do I receive a ResultSet from a stored procedure?

# How do I retrieve a whole row of data at once, instead of calling an individual ResultSet.getX.X.X method for each column?

# How do I set properties for a JDBC driver and where are the properties stored?

# How do I start debugging problems related to the JDBC API?

# How do I write Greek ( or other non-ASCII/8859-1 ) characters to a database?

# How do you handle your own transaction ?

# How does a custom RowSetReader get called from a CachedRowSet?

# How does one get column names for rows returned in a ResultSet?

# How does the Java Database Connectivity (JDBC) work?

# How many types of JDBC Drivers are present and what are they?

# How to insert and delete a row programmatically? (new feature in JDBC 2.0)

# How to move the cursor in scrollable resultsets?(new feature in JDBC 2.0)

# How to update a resultset programmatically? (new feature in JDBC 2.0)

# I have an application that queries a database and retreives the results into a

# I need to have result set on a page where the user can sort on the column headers. Any ideas?

# I would like to download the JDBC-ODBC Bridge for the Java 2 SDK, Standard Edition (formerly JDK 1.2). I'm a beginner with the JDBC API, and I would like to start with the Bridge. How do I do it?

# If I use the JDBC API, do I have to use ODBC underneath?

# Is is possible to open a connection to a database with exclusive mode with JDBC?

# Is the JDBC-ODBC Bridge multi-threaded?

# Is there a practical limit for the number of SQL statements that can be added to an instance of a Statement object
# JTable ...

# Many connections from an Oracle8i pooled connection returns statement closed. I am using import oracle.jdbc.pool.* with thin driver. If I test with many simultaneous connections, I get an SQLException that the statement is closed. How can I overwrite blob data in an Oracle database? ...

# Once I have the Java 2 SDK, Standard Edition, from Sun, what else do I need to connect to a database?

# The java.sql package contains mostly interfaces. When and how are these

# There is a method getColumnCount in the JDBC API. Is there a similar method to find the number of rows in a result set?

# Update fails without blank padding. Alhough a particular row is present in the database for a given key, executeUpdate() shows 0 rows updated and, in fact, the table is not updated. If I pad the Key with spaces for the column length (eg if the key column is 20 characters long, and key is msgID, length 6, I pad it with 14 spaces), the update then works!!! Is there any solution to this problem without padding?What isolation level is used by the DBMS when inserting, updating and

# Whan happens when I close a Connection application obtained from a connection Pool? How does a connection pool maintain the Connections that I had closed through the application?

# What JDBC objects generate SQLWarnings?

# What are four types of JDBC driver?

# What are stored procedures?

# What are the common tasks of JDBC?

# What are the components of the JDBC URL for Oracle's "thin" driver and how do I use them?

# What are the considerations for deciding on transaction boundaries?

# What are the different JDB drivers available?

# What are the standard isolation levels defined by JDBC?

# What are the steps required to execute a query in JDBC?

# What are the two major components of JDBC?

# What causes the "No suitable driver" error?

# What does Class.forName return?

# What does it mean to "materialize" data?

# What does normalization mean for java.sql.Date and java.sql.Time?

# What does setFetchSize() really do?

# What driver should I use for scalable Oracle JDBC applications?

# What is Connection pooling?

# What is Connection?

# What is DML?

# What is DriverManager ?

# What is JDBC Driver ?

# What is JDBC Driver interface?

# What is JDBC?

# What is JDO?

# What is Metadata and why should I use it?

# What is a JDBC 2.0 DataSource?

# What is a ResultSet ?

# What is an SQL Locator?

# What is cold backup, hot backup, warm backup recovery?

# What is new in JDBC 2.0?

# What is optimistic concurrency?

# What is pessimistic concurrency?

# What is the JDBC syntax for using a date literal or variable in a standard Statement?

# What is the JDBC syntax for using a literal or variable in a standard Statement?

# What is the advantage of denormalization?

# What is the advantage of using a PreparedStatement?

# What is the best way to generate a universally unique object ID? Do I need to

# What is the difference between client and server database cursors?

# What is the difference between setMaxRows(int) and SetFetchSize(int)? Can either reduce processing time?

# What is the fastest type of JDBC driver?

# What is the most efficient method of replicating data betwen databases using JDBC?

# What is the query used to display all tables names in SQL Server (Query analyzer)?

# What is the significance of DataBaseMetaData.tableIndexStatistics? How to

# What scalar functions can I expect to be supported by JDBC?

# What types of DataSource objects are specified in the Optional Package?

# What's the JDBC 3.0 API?

# What's the best way, in terms of performance, to do multiple insert/update statements, a PreparedStatement or Batch Updates?

# What's the fastest way to normalize a Time object?

# When I intersperse table creation or other DDL statements with DML statements ....

# When an SQL select statement doesn't return any rows, is an SQLException thrown?

# Where can I find info, frameworks and example source for writing a JDBC driver?

# Which Java and java.sql data types map to my specific database types?

# Which is the preferred collection class to use for storing database result sets?

# Which type of JDBC driver is the fastest one?

# Why can't I invoke the ResultSet methods afterLast and beforeFirst when the method next works?

# Why can't Tomcat find my Oracle JDBC drivers in classes111.zip?

# Why do I have to reaccess the database for Array, Blob, and Clob data?

# Why does the ODBC driver manager return 'Data source name not found and no default driver specified Vendor: 0' How to use JDBC to connect Microsoft Access?

# Why doesn't JDBC accept URLs instead of a URL string?

# Why isn't the java.sql.DriverManager class being found?

# Why should I consider optimistic versus pessimistic approaches to database

# alias) are present in a particular database?

Mainframes Interview questions-JCL interview question and answers

Mainframes Interview questions-JCL interview question and answers
What is GDG?
What does the statements: typrun=scan and
Why do you use a control card?
What is a procedure?
What is the meaning of the EXEC statement keyword,
What is the use of DSNDB07?
What is a Dummy Utility and what it does?
What does a disposition of (NEW, CATLG, KEEP) mean?
How do you restart a step in JCL?
What is SE37?
The maximum number of in-stream procedure you
Describe the EXEC statement, its meaning, syntax
What is meant by S0C7 system abend code?
What does TIME=1440 mean?
What is the difference between static call &
What you mean by skeleton JCL?
How is the keyword DUMMY used in JCL?
How much space OS allocates when you create
What is the max block size for a Tape file?
How do you skip a particular step in a proc/JOB?
How do you submit JCL via a COBOL program?
What is COND=ONLY?
How to get cursor position from system in CICS
What is MOD and when would you use it?
Which table PLAN is registered in?
What does the TIME parameter signify?
What happens if both JOBLIB and STEPLIB
What is a COND parameter in JCL?
How are datasets concatenated?
How do you create a temporary dataset? Where
What is a PROC?
How can you trap abends in the JCL?
What is 'S0C7' abend?
What is DATACOM db?
How to change default PROCLIB?
What is the DD statement for a output file?
Explain concatenating datasets?
What does S0C4 error mean?
What is SD37?
What is the error code SOC01 indicate?
What is model dataset label (Model DSCB)?
What do you do if you do not want to keep all
What are the keywords associated with DCB?
For how long a job can be executed continuously
Which is the most widely used batch performance
Can you code in stream data in a PROC?
How is a new GDG coded?
Describe the JOB statement, its meaning, syntax
How many positional parameters are there in job
What is NOTCAT?
What are the differences between JES2 & JES3?
What is the difference between specifying DISP=OLD
How do you submit JCL via a COBOL program?
What does a disposition of (NEW, CATLG, DELETE) mean?
What is the difference between an in stream and
What is the difference between BLKSIZE and LRECL?
How much is memory space involved, when we
What is order of searching of the libraries in a JCL?
How do you submit a JCL under CICS environment?
How is a GDG base created?
What is the difference between primary and
What are the kinds of job control statements?
What is the improvement to COND= in the latest
How do you submit a JCL under CICS environment?
What is primary allocation for a dataset?
What is the meaning of keyword in JCL?
How do you designate a comment in JCL?
What are three parameters you can specify on
How do you override a specific DDNAME/SYSIN
What is the difference between catalogue
What does SYSIN * indicate?
What does IEBGENER do?
What is a GDG?
How is a dataset passed from one step to another?
How do you restart a PROC from a particular step?
What is RESTART? How is it invoked?
What is QSAM error usually when it is occurs?
What is COND=EVEN?
How many parameters are there to a DISP
How do you send the output of a COBOL
When should DISP=MOD is used?
When should DISP=MOD is used?
What is the difference between specifying DISP=OLD
What is the purpose of include statement in a JCL?
What is SB37?
What are the maximum and minimum sizes of
What are three major types of JCL statements?
How are GDG s concatenated?
What are the basic JCL Statements for a Job?
How many types of libraries are there in JCL?
What is the difference between the JOBLIB
What is a GDG? How is it referenced? How
How do you pass parameters to the program
What is S322 abend?
Write a jcl to execute a job by 7 a.m on
What is a Generation Data Group (GDG)?
What is DISP = (NEW, PASS, DELETE)?
What is the difference between a symbolic and
How to pass the temp dataset form one JOB
What are the valid DSORG values?
What is STEPLIB, JOBLIB? What is it used for?
How many extents are possible for a sequential
What is the OS precedence for obtaining that
What do you mean by spooling? Expand SPOOL?
What do you feel makes a good program?
How do you check the syntax of a JCL without
How do you access a file that had a disposition of KEEP?
Describe the DD statement, its meaning, syntax
What is the purpose of the PARM keyword in
What is DSNDB06?
Can we browse or edit the GDG dataset if it is
How to execute a set of JCL statements from

Micro processor Interview questions

• What are the various registers in 8085? - Accumulator register, Temporary register, Instruction register, Stack Pointer, Program Counter are the various registers in 8085 . 
• In 8085 name the 16 bit registers? - Stack pointer and Program counter all have 16 bits.
• What are the various flags used in 8085? - Sign flag, Zero flag, Auxillary flag, Parity flag, Carry flag.
• What is Stack Pointer? - Stack pointer is a special purpose 16-bit register in the Microprocessor, which holds the address of the top of the stack.
• What is Program counter? - Program counter holds the address of either the first byte of the next instruction to be fetched for execution or the address of the next byte of a multi byte instruction, which has not been completely fetched. In both the cases it gets incremented automatically one by one as the instruction bytes get fetched. Also Program register keeps the address of the next instruction.
• Which Stack is used in 8085? - LIFO (Last In First Out) stack is used in 8085.In this type of Stack the last stored information can be retrieved first.
• What happens when HLT instruction is executed in processor? - The Micro Processor enters into Halt-State and the buses are tri-stated.
• What is meant by a bus? - A bus is a group of conducting lines that carriers data, address, & control signals.
• What is Tri-state logic? - Three Logic Levels are used and they are High, Low, High impedance state. The high and low are normal logic levels & high impedance state is electrical open circuit conditions. Tri-state logic has a third line called enable line.
• Give an example of one address microprocessor? - 8085 is a one address microprocessor.
• In what way interrupts are classified in 8085? - In 8085 the interrupts are classified as Hardware and Software interrupts.
• What are Hardware interrupts? - TRAP, RST7.5, RST6.5, RST5.5, INTR.
• What are Software interrupts? - RST0, RST1, RST2, RST3, RST4, RST5, RST6, RST7.
• Which interrupt has the highest priority? - TRAP has the highest priority.
• Name 5 different addressing modes? - Immediate, Direct, Register, Register indirect, Implied addressing modes.
• How many interrupts are there in 8085? - There are 12 interrupts in 8085.
• What is clock frequency for 8085? - 3 MHz is the maximum clock frequency for 8085.
• What is the RST for the TRAP? - RST 4.5 is called as TRAP.
• In 8085 which is called as High order / Low order Register? - Flag is called as Low order register & Accumulator is called as High order Register.
• What are input & output devices? - Keyboards, Floppy disk are the examples of input devices. Printer, LED / LCD display, CRT Monitor are the examples of output devices.
• Can an RC circuit be used as clock source for 8085? - Yes, it can be used, if an accurate clock frequency is not required. Also, the component cost is low compared to LC or Crystal.
• Why crystal is a preferred clock source? - Because of high stability, large Q (Quality Factor) & the frequency that doesn’t drift with aging. Crystal is used as a clock source most of the times.
• Which interrupt is not level-sensitive in 8085? - RST 7.5 is a raising edge-triggering interrupt.
• What does Quality factor mean? - The Quality factor is also defined, as Q. So it is a number, which reflects the lossness of a circuit. Higher the Q, the lower are the losses.
• What are level-triggering interrupt? - RST 6.5 & RST 5.5 are level-triggering interrupts.