Working with very large text data and CLOB column

Question

According to documentation CLOB and NCLOB datatype columns, can store up to 8 terabytes of character data.

I have text, which contains 100 000 character, how can I

Answer 1

You should use the dbms_lob package, the procedure to add some string to the clob is dbms_lob.append.

DBMS_LOB documentation

declare
  c1 clob;
  c2 varchar2(32000);
begin
  c1 := 'abc';
  c2 := 'text, which contains 32 000 characters';
  dbms_lob.append(c1, c2);
  c2 := 'some more text, which contains 32 000 characters';
  dbms_lob.append(c1, c2);
  insert into t1 values (c1);
end;

Answer 2

I found this question while Googling how to append data to a CLOB. For my particular problem, I'm using a legacy PL/SQL system where I can't make use of the dbms_lob package, so I thought that I would share my answer for the benefit of others in my situation.

Solution: Use Oracle's CONCAT function in aSELECTquery, theCONCATfunction works for theCLOB` data type. For example (using @AlenOblak's example):

declare
  c1 clob;
  c2 varchar2(32000);
begin
  c1 := 'abc';
  c2 := 'text, which contains 32 000 characters';
  SELECT CONCAT(c1, c2) INTO c1 FROM DUAL;
  c2 := 'some more text, which contains 32 000 characters';
  SELECT CONCAT(c1, c2) INTO c1 FROM DUAL;
  insert into t1 values (c1);
end;

Hope that helps.

Answer 3

I have resolve this case with Data Import feature in Oracle SQL Developer:

1. Make .dsv file with your large string and other attributes.
2. Just rclick on table and choose 'Data Import'
3. Choose your file
4. In Data Import Wizard Step1: select rigth Delimeter, Line Terminator, Row Limit, Encloser characters etc.
5. Step2: Import Method=Insert, Step3: Map file and table columns to each other
6. Step4: Run the Data Import