Oracle Tutorials

Home| Forums | Join Google Group | Join Yahoo Group | Jobs

Earn Money
Trading Forex Online
  Paramount Airways
  Free Data Recovery
Cargo
Job Portal
  HSBC Investment
Management
Cheap Web Hosting
  Make Trip
  Cheap Air Travel
Leisure Hotel
  Free Air Travel
  Mutual Fund Informations
Cheapest Cellular Plan
Free Sexy Indians
  Call Center Software
  Hot Indian

Programming Help | Homework Help | Counseling
Astrology Advice | Tarot Advice | Parenting
Dating Advice | Love Advice | Divorce Advice
Legal Advice | Debt Advice | Career Advice
or more columns in one table are equal to one or more columns in the second table. What are various constraints used in SQL ? NULL, NOT NULL, CHECK, DEFAULT What are different Oracle database objects ? TABLES, VIEWS, INDEXES, SYNONYMS, SEQUENCES, TABLESPACES etc What is difference between Rename and Alias ? Rename is a permanent name given to a table or column whereas Alias is a temporary name given to a table or column which do not exist once the SQL statement is executed. What is a view ? A view is stored procedure based on one or more tables, it's a virtual table. What are various privileges that a user can grant to another user ? SELECT, CONNECT, RESOURCES What is difference between UNIQUE and PRIMARY KEY constraints ? A table can have only one PRIMARY KEY whereas there can be any number of UNIQUE keys. The columns that compose PK are automatically define NOT NULL, whereas a column that compose a UNIQUE is not automatically defined to be mandatory must also specify the column is NOT NULL. Can a primary key contain more than one columns ? Yes How you will avoid duplicating records in a query ? By using DISTINCT What is difference between SQL and SQL*PLUS ? SQL*PLUS is a command line tool where as SQL and PL/SQL language interface and reporting tool. Its a command line tool that allows user to type SQL commands to be executed directly against an Oracle database. SQL is a language used to query the relational database(DML,DCL,DDL). SQL*PLUS commands are used to format query result, Set options, Edit SQL commands and PL/SQL. Which datatype is used for storing graphics and images ? LONG RAW data type is used for storing BLOB's (binary large objects). How will you delete duplicating rows from a base table ? DELETE FROM table_name A WHERE rowid>(SELECT min(rowid) from table_name B where B.table_no=A.table_no); CREATE TABLE new_table AS SELECT DISTINCT * FROM old_table; DROP old_table RENAME new_table TO old_table DELETE FROM table_name A WHERE rowid NOT IN (SELECT MAX(ROWID) FROM table_name GROUP BY column_name)