I have a task to compare some Teradata Views with actual Oracle Tables.
I need a script for that.I have taken Java approach in which I connect to a specific schema from Oracle and then call the SELECT * FROM all_tables order by TABLE_NAME query and write this into a file.
I do the same for other schema but now my problem is Teradata.
Can you people please suggest me some script or query by which I can get proper details like it does with Oracle.
There is no complex Java Code but if you still want I can post it.
Edited:
Okay now I have a schema in Oracle which has all the tables.so views for those tables are created in Teredata.
I have to compare oracle tables and Teradata views every morning and send the differances.
So I use SELECT * FROM all_tables order by TABLE_NAME in Oracle and for Teradata I use SELECT * FROM dbc.tables WHERE tablekind='V' AND databasename='SCHEMA' order by TableName so now when I compare them I dont get accurate results, so I wanted to know does any script exists or how do I approach.
If your question is "How can I programmatically determine the structure of a view in Teradata?", then this should be a step in the right direction: HELP VIEW yourviewname;.
To get a list of views on a given table:
SELECT TableName
FROM DBC.Tables
WHERE Tablekind = 'V'
AND requestText LIKE '%yourtablename%'
GROUP BY 1
ORDER BY 1;
This information was gleaned from the official Teradata forums. You might also be interested in the Teradata users manuals. (Select your release version on the top right.)
Related
I am using Oracle. A legacy script created our table structure.
When I try to select from, say, tableA, sql developer very helpfully finds the table as I type. But instead of filling in a valid user it shows me (eg)
SELECT * FROM not_found?.tableA
I'm guessing the script pulled the user incorrectly, but the table seems to actually exist (or it wouldn't fill in the user, n'est ce pas?). Does anyone know WHERE THE HECK IT IS?
Use this to find the schema in which the table is:
select owner from all_tables where table_name = 'TABLEA';
I am developing a java app which can connect to oracle database and selecting column names from any tables, after selecting columns i have to query the data from those tables which the user select in my java app, now my question is how can i join all tables in the database so that query returns data successfully, i want to connect to any oracle schema to a specific, i will make the logic in java, but i am unable to find the query which can extract the data from all tables, i tried natural join among all tables but it has dependency of having same name of connecting columns. so i want to know any generic way which can work in all conditions.
As others have mentioned.. it seems that there are other tools out there that you probably should leverage prior to trying to roll your own complex solution.
With that said if you wish to roll your own solution you could look into using some of oracle's dictionary tables. Such as:
Select * from all_tables;
Select * from all_tab_cols;
How can I find out which tables I have in CockroachDB? I tried looking for my schema and couldn't find that, so I'm not sure how to find out which tables I've already created or what their columns are.
First, you'll need to find your databases (which are CockroachDB's equivalent to PostgreSQL's schemas) using either:
MySQL-style SHOW DATABASES statement
PostgreSQL-style by querying information_schema.schemata. For example:
SELECT schema_name FROM information_schema.schemata;
Once you have the database name, you can find the tables using either:
MySQL-style SHOW TABLES statement
PostgreSQL-style by querying information_schema.tables. For example:
SELECT table_name FROM information_schema.tables WHERE table_schema = '[database to check]';
Once you find the tables, you can get more information about them using SHOW COLUMNS FROM [table] or the information_schema database.
Hi I m new to oracle using 11g exprs edition and familiar with mysql. We can use the below code to display all databases in mysql
show databases;
What is the corresponding command in Oracle. Or how can i display all databases. Also We have
use mydatabase;
to chanage database in mysql. How can i change database in oracle. I tried to display all owners and their tables using the following command
select table_name, owner from all_tables;
It working fine. But when I tried to display tables I have created, by adding a where cluase
select table_name, owner from all_tables where owner='root';
it shows no rows were selected. Why this happens? Also I am facing the same problem with most of the queries when using the where clause. Without where clause it works fine. but when using it, the result is no rows selected for example
select * from all_tab_comments where owner='root';
select constraint_name, constraint_type from user_constraints where table_name='location';
Is there anything special in oracle for where clause or the problem with my query.
Your username is very unlikely to be root; it could however be ROOT, in which case you could do:
select table_name, owner from all_tables where owner='ROOT';
The owner name is case-sensitive, and all objects including users and table names are upper-case by default (unless they're created with double-quotes, which is a bad idea). If you're connected as that user, to see only your own tables you can also do:
select table_name from user_tables;
And there is the dba_tables view which also shows you tables you don't have permissions on, but you can only see that with elevated privileges.
Oracle doesn't have 'databases' in the same sense as other products. You probably means schemas, as the logical grouping of objects. And schemas and users are essentially synonymous.
To get a list of all schemas you can query dba_users (if you have the right privileges), or to get a list of schemas that have objects - as you may have users who only use objects in other schemas - you can do:
select distinct owner from dba_objects;
... or all_objects to again only see things you have permissions for. To see what kind of objects:
select owner, object_type, count(*) from dba_objects group by owner, object_type;
The documentation explains the static data dictionary views which hold all of this information. You won't be able to see all of them though, unless you're connected as a privileged user.
There will be a lot of differences between the two products; you might be better off trying to find a tutorial that works through them rather than using trial and error and trying to understand what's gone wrong at each step. Or at least familiarise yourself with the Oracle documentation so you can research issues.
First, there is going to be a terminology difference when you change platforms. What MySQL calls a "database" is most similar to what Oracle calls a "schema". If you are using Oracle XE, you can only have one database (using Oracle terminology) on the machine. You can have many schemas within that database.
The owner in all_tables is the name of the schema that owns the table. Assuming that you created an Oracle user root (which seems like an odd choice for a database user) and assuming that you did not create a case-sensitive user name in all lower case (which would create a ton of issues down the line), the owner will always be upper-case.
SELECT owner, table_name
FROM all_tables
WHERE owner = 'ROOT'
In Oracle, you do not generally change from one schema to another. You either fully qualify the table name
SELECT *
FROM schema_name.table_name
or you create synonyms (public or private) for objects that you want to reference
CREATE SYNONYM synonym_name
FOR schema_name.table_name;
SELECT *
FROM synonym_name
If you really want to, however, you can change your current schema for name resolution purposes
ALTER SESSION SET current_schema = <<schema name>>
use the view : tabs
select * from tabs;
Sounds pretty easy query the column names from a table, right? Indeed there is a answer to this question How can I get column names from a table in Oracle?
The main issue is that the table belongs to another user. My user is just for integration and I don't have any database privileges.
So I'm able to do some query like: SELECT * FROM anotherUser.THE_TABLE;
But something like SELECT * FROM USER_TAB_COLUMNS return no rows.
Perhaps I can create queries over all_tab_columns, Are there another faster options without procedures?
*It´s a oracle database!
SELECT *
FROM ALL_TAB_COLUMNS
WHERE OWNER='ANOTHERUSER'
AND TABLE_NAME='THE_TABLE';
Should get you there if you have privileges on the table.