oracle sql concatenate column values

--Create table/*create table test_table (STUDENT VARCHAR2 ($), SUBJECT VARCHAR2 (+), GRADE number) Tablespace Syste M pctfree pctused Initrans 1 Maxtrans 255 storage (initial 64K minextents 1 Maxextents Unlimited); *//*insert into test_table (student, Subject, Grade) values (' Zhang San ', ' languages ', ') insert into test_table (student, Subject, G Rade) VALUES (' Zhang San ', ' Math ', ' Max ') insert in

In SQL Server, there is a function replicate () can implement the column chart effect, essentially using the number of occurrences of characters to control the length of the column chart, the effectIf you want to achieve the same effect within Oracle, you need to write a function yourself:CREATE OR REPLACE FUNCTION kth

ORACLE cannot use variables as column names and table names some of the individual validations are:1 DECLARE2Ename1 Emp.ename%TYPE;3TYPE Index_emp_type is TABLE of VARCHAR2( -)INDEX byPls_integer;4 index_emp Index_emp_type;5 BEGIN 6Index_emp (1) := 'E.ename';7 SELECTIndex_emp (1) intoEname1 fromEMP EWHEREE.empno=7369;8 EXECUTEIMMEDIATE'Select' ||Index_emp (1)|| 'From emp e where e.empno=7369' intoename1;