I am using json_arrayagg in Oracle to create a json array from multiple rows in a table. Here are details:
create table classInfo (classId integer, category CLOB);
insert into classInfo(1, '{"category":"AAA"}');
insert into classInfo(2, '{"category":"BBB"}');
commit;
select json_arrayagg(category returning clob) from classInfo;
The output has a \ along with " as following:
["{\"category\""AAA\"}", "{\"category\":\"BBB\"}"]
How can I get ride off those \ ?
Thanks in advance!
Use FORMAT JSON:
select json_arrayagg(category FORMAT JSON RETURNING CLOB) from classInfo;
Which outputs:
JSON_ARRAYAGG(CATEGORYFORMATJSONRETURNINGCLOB)
[{"category":"AAA"},{"category":"BBB"}]
db<>fiddle here
Related
I have an object type: create type t_ref_rec is object(id number, name varchar2(256));
And a table type: create type t_ref_tbl is table of t_ref_rec;
I parse JSON onto a collection like this:
declare
var_ref_tbl t_ref_tbl;
begin
...
select
t_ref_rec(id, name)
bulk collect into
var_ref_tbl
from
json_table
(
'[{"id":1, "name":"one"}, {"id":2, "name":"two"}]',
'$[*]'
columns
(
id number path '$.id',
name varchar2 path '$.name'
)
);
....
end;
Is there a better way to parse data from JSON into a collection of t_ref_tbl type?
If you're on 19c or higher, the best way is to state your object as the return type for a JSON_value call and the database will map it for you:
create type t_ref_rec is object(id number, name varchar2(256));
/
create type t_ref_tbl is table of t_ref_rec;
/
select json_value (
'[{"id":1, "name":"one"}, {"id":2, "name":"two"}]',
'$' returning t_ref_tbl
) obj
from dual;
OBJ(ID, NAME)
---------------------------------------------------
T_REF_TBL(T_REF_REC(1, 'one'), T_REF_REC(2, 'two'))
The on mismatch clause enable you to define what happens if there's a difference between the JSON document and the object type.
I have function which returns column names and i am trying to use the column name as part of my select statement, but my results are coming as column name instead of values
FUNCTION returning column name:
get_col_name(input1, input2)
Can И use this query to the results of the column from table -
SELECT GET_COL_NAME(input1,input2) FROM TABLE;
There are a few ways to run dynamic SQL directly inside a SQL statement. These techniques should be avoided since they are usually complicated, slow, and buggy. Before you do this try to find another way to solve the problem.
The below solution uses DBMS_XMLGEN.GETXML to produce XML from a dynamically created SQL statement, and then uses XML table processing to extract the value.
This is the simplest way to run dynamic SQL in SQL, and it only requires built-in packages. The main limitation is that the number and type of columns is still fixed. If you need a function that returns an unknown number of columns you'll need something more powerful, like the open source program Method4. But that level of dynamic code gets even more difficult and should only be used after careful consideration.
Sample schema
--drop table table1;
create table table1(a number, b number);
insert into table1 values(1, 2);
commit;
Function that returns column name
create or replace function get_col_name(input1 number, input2 number) return varchar2 is
begin
if input1 = 0 then
return 'a';
else
return 'b';
end if;
end;
/
Sample query and result
select dynamic_column
from
(
select xmltype(dbms_xmlgen.getxml('
select '||get_col_name(0,0)||' dynamic_column from table1'
)) xml_results
from dual
)
cross join
xmltable
(
'/ROWSET/ROW'
passing xml_results
columns dynamic_column varchar2(4000) path 'DYNAMIC_COLUMN'
);
DYNAMIC_COLUMN
--------------
1
If you change the inputs to the function the new value is 2 from column B. Use this SQL Fiddle to test the code.
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 am designing a database in oracle 11g. I have designed a table with fields,
CUST_ID, NUMBER(5) //this is a foreign key
Review, BLOB //to store big strings
Date, SYSDATE
now when i'm trying to insert data in the table like-
insert into "ReviewTable" values ( 3, 'hello, this is the first review',SYSDATE)
it gives [Err] ORA-01465: invalid hex number.
If someone can help me with the error?
you cast your string into BLOB, you can do this via package utl_raw.cast_to_raw or convert varchar to clob via to_clob('mystring') and then use procedure DBMS_LOB.convertToBlob in your code
but if you are going to use the fields for string why don`t save them as a CLOB?
Here are 2 examples below with BLOB and CLOB fields
BLOB
create table ReviewTable( CUST_ID NUMBER(5)
,Review BLOB
,Dt Date);
insert into ReviewTable values ( 3, utl_raw.cast_to_raw('hello, this is the first review'),SYSDATE);
CLOB
create table ReviewTable2( CUST_ID NUMBER(5)
,Review CLOB
,Dt Date);
insert into ReviewTable2 values ( 3, 'hello, this is the first review',SYSDATE);
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