 Related Questions Self join-Its a join foreign key of a table references the same table. Outer Join--Its a join condition used where One can query all the rows of one of the tables in the join condition even though they Latest Answer : Please let me know various joins available and description for every joinRegards,sireesha ... 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. Latest Answer : Rename means give the new name to existed objects alise is use to refrence to objects ... A view is stored procedure based on one or more tables, it’s a virtual table. Latest Answer : View
View is logical table based on one are more table join and named as viewname
View is not stored in database View is used to perform complex query, View Object,
View support, LOB, varray, Nested Tables Should have CREATE ... 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 Latest Answer : Primay Key Unique key----------- ... delete from table_name where rowid not in (select max(rowid) from table group by duplicate_values_field_name); ordelete duplicate_values_field_name dv from table_name ta where rowid Latest Answer : Delete table_name t1where rowid>(select rowid from table_name t2)and t1.column1=t2.column1 ... It is a column that is not an actual column in the table.eg USER, UID, SYSDATE, ROWNUM, ROWID, NULL, AND LEVEL. Latest Answer : Pseudo columns is not actula column in the table. it behaves like table columnwe can retivesv values of pseduo column but can not insert,update or delete value in that.has two data type 1. rowid 2. urowidrow id uniqely identify row in databaseEXM ... Suppose a customer table is having different columns like customer no, payments.What will be the query to select top three max payments? SELECT customer_no, payments from customer C1WHERE 3 SELECT DISTINCT (a.sal) FROM EMP A WHERE &N = (SELECT COUNT (DISTINCT (b.sal)) FROM EMP B WHERE a.sal Latest Answer : SELECT v.sal FROM (SELECT TO_NUMBER(salary) sal,rank() over (ORDER BY TO_NUMBER(salary) DESC) ranksal FROM employee ORDER BY 1 DESC)v WHERE v.ranksal=6 Pls note where 6 is the ranknumber ... A bad answer is count them (SELECT COUNT(*) FROM table_name)A good answer is :-'By generating SQL to ANALYZE TABLE table_name COUNT STATISTICS by querying Oracle System Catalogues (e.g. USER_TABLES Latest Answer : If you want to find the number of Rows in table SELECT COUNT(*) FROM EMP;This is valid query ... select level, min('col_name') from my_table where level = '&n' connect by prior ('col_name') Latest Answer : TO find out nth LOWEST value, e.g. salary from emp table without using ROWNUM & DESC/ASCSELECT DISTINCT (a.sal) FROM EMP A WHERE &N = (SELECT COUNT (DISTINCT (b.sal)) ...
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