I need to be able to reconstruct a table column by using the column data in DBA_TAB_COLUMNS, and so to develop this I need to understand what each column refers to. I'm looking to understand what DATA_TYPE_MOD is -- the documentation (http://docs.oracle.com/cd/B19306_01/server.102/b14237/statviews_2094.htm#I1020277) says it is a data type modifier, but I can't seem to find any columns with this field populated or any way to populate this field with a dummy column. Anyone familiar with this field?
Data_type_mod column of the [all][dba][user]_tab_columns data dictionary view gets populated when a column of a table is declared as a reference to an object type using REF datatype(contains object identifier(OID) of an object it points to).
create type obj as object(
item number
) ;
create table tb_1(
col ref obj
)
select t.table_name
, t.column_name
, t.data_type_mod
from user_tab_columns t
where t.table_name = 'TB_1'
Result:
table_name column_name data_type_mod
-----------------------------------------
TB_1 COL REF
Oracle has a PL/SQL package that can be used to generate the DDL for creating a table. You would probably be better off using this.
See GET_DDL on http://docs.oracle.com/cd/B19306_01/appdev.102/b14258/d_metada.htm#i1019414
And see also:
How to get Oracle create table statement in SQL*Plus
Related
I have been trying to create a new table by using below query :
"Create table d1_details_test2
as
select * from d1_details"
this above query gives me an error :
actually "d1_details" table has one column which has "Long" datatype and i cannot change it.
so i want to know the any other way to create the table.
Thanks
The long data type is subject to many restrictions. Create table as select is one of these.
You can get around it by applying to_lob in the select, which converts it to a clob:
create table views as
select view_name, text from user_views;
ORA-00997: illegal use of LONG datatype
create table views as
select view_name, to_lob ( text ) lob
from user_views;
desc views
Name Null? Type
VIEW_NAME VARCHAR2(128)
LOB CLOB
Thank you for reply guys. I kind of solved my problem.
I used to try to update data with ref cursor in dynamic SQL using "where current of" but I now know that won't work.
Then I tried to use %rowtype to store both 'id' and 'clob' in one variable for future updating but turns out weak ref cursor can't use that type binding either.
After that I tried to use record as return of an ref cursor and that doesn't work on weak cursor either.
On the end, I created another cursor to retrieve 'id' separately along with cursor to retrieve 'clob' on the same time then update table with that id.
I'm now working on a Oracle data cleaning task and have a requirement like below:
There are 38 tables(maybe more in the future) and every table has one or multiple column which type is Clob. I need to find different keyword in those columns and according to a logic return binary label of the column and store it in a new column.
For example, there is a table 'myTable1' which has 2 Clob columns 'clob1' and 'clob2'. I'd like to find keyword 'sky' from those columns and store '0'(if not found) or '1'(if found) in two new columns 'clob1Sky','clob2Sky'.
I know if I could write it on a static way which will provide higher efficiency but I have to modify it for those very similar tasks every time. I want save some time on this so I'm trying to write it in a reusable way and not binding to certain table.
But I met some problem when writing the program. My program is like below:
create or replace PACKAGE body LABELTARGETKEYWORD
as
/**
#param varcher tableName: the name of table I want to work on
#param varchar colName: the name of clob column
#param varchar targetWord: the word I want to find in the column
#param varchar newColName: the name of new column which store label of clob
*/
PROCEDURE mainProc(tableName varchar, colName varchar,targetWord varchar,newColName varchar2)
as
type c_RecordCur is ref cursor;
c_sRecordCur c_recordCur;
/*other variables*/
begin
/*(1) check whether column of newColName exist
(2) if not, alter add table of newColName
(3) open cursor for retrieving clob
(4) loop cursor
(5) update set the value in newColName accroding to func labelword return
(6) close cursor and commit*/
end mainProc;
function labelWord(sRecord VARCHAR2,targetWord varchar2) return boolean...
function ifColExist(tableName varchar2,newColName varchar2) return boolean...
END LABELTARGETKEYWORD;
Most DML and DDL are written in dynamic sql way.
The problem is when I write the (5) part, I notice 'Where current of' clause can not be used in a ref cursor or dynamic sql statement. So I have to change the plan.
I tried to use a record(rowid,label) to store result and alter the table later.(the table only be used by two people in my group, so there won't be problem of lock and data changes). But I find because I'm trying to use dynamic sql so actually I have to define ref cursor with return of certain %rowtype and basically all other variables, %type in dynamic sql statement. Which makes me feel my method has something wrong.
My question are:
If there a way to define %type in dynamic sql? Binding type to variable in dynamic SQL?
Could anybody give me a hint how to write that (5) part in dynamic SQL?
Should not I design my program like that?
Is it not the way how to use dynamic SQL or PLSQL?
I'm very new to PL/SQL. Thank you very much.
According to Tom Kyte's advice, to do it in one statement if it can be done in one statement, I'd try to use a single UPDATE statement first:
CREATE TABLE mytable1 (id NUMBER, clob1 CLOB,
clob2 CLOB, clob1sky NUMBER, clob2sky NUMBER )
LOB(clob1, clob2) STORE AS SECUREFILE (ENABLE STORAGE IN ROW);
INSERT INTO mytable1(id, clob1, clob2)
SELECT object_id, object_name, object_type FROM all_objects
WHERE rownum <= 10000;
CREATE OR REPLACE
PROCEDURE mainProc(tableName VARCHAR2, colName VARCHAR2, targetWord VARCHAR2, newColName VARCHAR2)
IS
stmt VARCHAR2(30000);
BEGIN
stmt := 'UPDATE '||tableName||' SET '||newColName||'=1 '||
'WHERE DBMS_LOB.INSTR('||colName||','''||targetWord||''')>1';
dbms_output.put_line(stmt);
EXECUTE IMMEDIATE stmt;
END mainProc;
/
So, calling it with mainProc('MYTABLE1', 'CLOB1', 'TAB', 'CLOB1SKY'); fires the statement
UPDATE MYTABLE1 SET CLOB1SKY=1 WHERE DBMS_LOB.INSTR(CLOB1,'TAB')>1
which seems to do the trick:
SELECT * FROM mytable1 WHERE clob1sky=1;
id clob1 clob2 clob1sky clob2skiy
33 I_TAB1 INDEX 1
88 NTAB$ TABLE 1
89 I_NTAB1 INDEX 1
90 I_NTAB2 INDEX 1
...
I am not sure with your question-
If this job is suppose to run on daily or hourly basis ,running query through it will be very costly. One thing you can do - put all your clob data in a file and save it in your server(i guess it must be linux). then you can create a shell script and schedule a job to run gerp command and fetch your required value and "if found then update your table".
I think you should approaches problem another way:
1. Find all columns that you need:
CURSOR k_clobs
select table_name, column_name from dba_tab_cols where data_type in ('CLOB','NCLOB');
Or 2 cursor(you can build you query if you have more than 1 CLOB per table:
CURSOR k_clobs_table
select DISTINCT table_name from dba_tab_cols where data_type in ('CLOB','NCLOB');
CURSOR k_clobs_columns(table_namee varchar(255)) is
select column_name from dba_tab_cols where data_type in ('CLOB','NCLOB') and table_name = table_namee;
Now you are 100% that column you are checking is clob, so you don't have to worry about data type ;)
I'm not sure what you want achieve, but i hope it may help you.
I'm completely new to Hive and Stack Overflow. I'm trying to create a table with complex data type "STRUCT" and then populate it using INSERT INTO TABLE in Hive.
I'm using the following code:
CREATE TABLE struct_test
(
address STRUCT<
houseno: STRING
,streetname: STRING
,town: STRING
,postcode: STRING
>
);
INSERT INTO TABLE struct_test
SELECT NAMED_STRUCT('123', 'GoldStreet', London', W1a9JF') AS address
FROM dummy_table
LIMIT 1;
I get the following error:
Error while compiling statement: FAILED: semanticException [Error
10044]: Cannot insert into target because column number type are
different 'struct_test': Cannot convert column 0 from struct to
array>.
I was able to use similar code with success to create and populate a data type Array but am having difficulty with Struct. I've tried lots of code examples I've found online but none of them seem to work for me... I would really appreciate some help on this as I've been stuck on it for quite a while now! Thanks.
your sql error. you should use sql:
INSERT INTO TABLE struct_test
SELECT NAMED_STRUCT('houseno','123','streetname','GoldStreet', 'town','London', 'postcode','W1a9JF') AS address
FROM dummy_table LIMIT 1;
You can not insert complex data type directly in Hive.For inserting structs you have function named_struct. You need to create a dummy table with data that you want to be inserted in Structs column of desired table.
Like in your case create a dummy table
CREATE TABLE DUMMY ( houseno: STRING
,streetname: STRING
,town: STRING
,postcode: STRING);
Then to insert in desired table do
INSERT INTO struct_test SELECT named_struct('houseno',houseno,'streetname'
,streetname,'town',town,'postcode',postcode) from dummy;
No need to create any dummy table : just use command :
insert into struct_test
select named_struct("houseno","house_number","streetname","xxxy","town","town_name","postcode","postcode_name");
is Possible:
you must give the columns names in sentence from dummy or other table.
INSERT INTO TABLE struct_test
SELECT NAMED_STRUCT('houseno','123','streetname','GoldStreet', 'town','London', 'postcode','W1a9JF') AS address
FROM dummy
Or
INSERT INTO TABLE struct_test
SELECT NAMED_STRUCT('houseno',tb.col1,'streetname',tb.col2, 'town',tb.col3, 'postcode',tb.col4) AS address
FROM table1 as tb
CREATE TABLE IF NOT EXISTS sunil_table(
id INT,
name STRING,
address STRUCT<state:STRING,city:STRING,pincode:INT>)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY '.';
INSERT INTO sunil_table 1,"name" SELECT named_struct(
"state","haryana","city","fbd","pincode",4500);???
how to insert both (normal and complex)data into table
I have a table that has one of its columns as a nested table.
I want to copy data of this table to another. How do we frame the INSERT clause for this seems challenging:
Consider. The field that is a nested table is phone_list whose type is a user defined type "TBL_PHONE_EXTN" which is a table of "typ_phone_extn".
CREATE OR REPLACE TYPE typ_phone_extn AS OBJECT
(phone_number VARCHAR2 (20), extension VARCHAR2 (10));
/
CREATE OR REPLACE TYPE tbl_phone_extn AS TABLE OF typ_phone_extn;
/
Obviously below fails: (with a ORA-00904: : invalid identifier)
INSERT INTO sch2.sub_pat_address (
pat_address_id,
pat_id,
**phone_list,**
last_updated_by
)
SELECT pat_address_id,
pat_id,
**phone_list,**
last_updated_by
FROM sch1.sub_pat_address ;
So i try:
SELECT pat_address_id,
pat_id,
**tbl_phone_extn(typ_phone_extn (phone_number,extension)),**
last_updated_by
FROM sch1.sub_pat_address, **table(phone_list)** ;
What this does is unnest the nested table. So i end up with more records than i want - meaning if a specific pat_address_id had a phone_list of 5 phone,extn combination this gives me 5 records that i cannot and should not be inserting.
So question is, how to keep the nest (nested table column) as-is and insert into the new table? Well, CTAS may be one option but that requires a whole new table instead of a INSERT. Any help will be greatly appreciated.
You can use the COLLECT function to reassemble the unnested elements into a nested table, casting that back to your actual collection type:
SELECT pat_address_id,
pat_id,
cast(collect(typ_phone_extn(phone_number,extension)) as tbl_phone_extn),
last_updated_by
FROM sch1.sub_pat_address, table(phone_list)
GROUP BY pat_address_id, pat_id, last_updated_by;
And you can then use that for your insert, obviously.
The only reason I can see you'd have a problem with your original simple insert would be if each schema had its own types and their tables were built using their own types. But then you'd get ORA-00932: inconsistent datatypes or ORA-01031: insufficient privileges rather than ORA-00904.
Even if you have privileges on the types across the schemas, Oracle UDTs have to be the exact same type - it's not enough for them to be constructed identically. If they are different entries in ALL_OBJECTS then they are not interchangeable.
I'm looking for the best way to change a data type of a column in a populated table. Oracle only allows changing of data type in colums with null values.
My solution, so far, is a PLSQL statement which stores the data of the column to be modified in a collection, alters the table and then iterates over the collection, restoring the original data with data type converted.
-- Before: my_table ( id NUMBER, my_value VARCHAR2(255))
-- After: my_table (id NUMBER, my_value NUMBER)
DECLARE
TYPE record_type IS RECORD ( id NUMBER, my_value VARCHAR2(255));
TYPE nested_type IS TABLE OF record_type;
foo nested_type;
BEGIN
SELECT id, my_value BULK COLLECT INTO foo FROM my_table;
UPDATE my_table SET my_value = NULL;
EXECUTE IMMEDIATE 'ALTER TABLE my_table MODIFY my_value NUMBER';
FOR i IN foo.FIRST .. foo.LAST
LOOP
UPDATE my_table
SET = TO_NUMBER(foo(i).my_value)
WHERE my_table.id = foo(i).id;
END LOOP;
END;
/
I'm looking for a more experienced way to do that.
The solution is wrong. The alter table statement does an implicit commit. So the solution has the following problems:
You cannot rollback after alter the alter table statement and if the database crashes after the alter table statement you will loose data
Between the select and the update users can make changes to the data
Instead you should have a look at oracle online redefinition.
Your solution looks a bit dangerous to me. Loading the values into a collection and subsequently deleting them fom the table means that these values are now only available in memory. If something goes wrong they are lost.
The proper procedure is:
Add a column of the correct type to the table.
Copy the values to the new column.
Drop the old column.
Rename the new column to the old columns name.