Guys is there any other way to determine a table exists other than below
select count(*) from <table> where rownum =1
select * from user_table where table_name=<table>
kindly let me know the best way to check whether a table exists using oracle sql.
Thanks for the answer , my requirement is to check from the first date of current month ie 01/12/2010 with table name in the format suresh_20101201 exists in the database, if not then it should check for table suresh_20101202 and thereon till suresh_20101231 . is it possible to do in oracle sql query.
You can do this (in oracle, in mssql there is a bit different):
select count(*)
from all_objects
where object_type in ('TABLE','VIEW')
and object_name = 'your_table_name';
In most sql servers there is a system domain where you can query for a table's existence. It's highly implementation specific though. For example, in recent versions of MySql:
SELECT table_name FROM INFORMATION_SCHEMA.TABLES
WHERE table_schema = 'db_name'
AND table_name LIKE 'whatever'
You need to ask your server's system catalog. Not sure what database you meant but for SQL Server it would be:
select * from sys.tables where name='your-table-name-'
Used this in Oracle SQL Developer:
SELECT COUNT(*) FROM DUAL WHERE EXISTS (
SELECT * FROM ALL_OBJECTS WHERE OBJECT_TYPE = 'TABLE' AND OWNER = 'myschema' AND OBJECT_NAME = 'your_table_name')
This will return either a 0 or 1 if your table exists or not in the ALL_OBJECTS records.
Below query can be triggered to Oracle for checking whether any Table present in DB or not:
SELECT count(*) count FROM dba_tables where table_name = 'TABLE_NAME'
Above query will return count 1 if table 'TABLE_NAME' is present in Database
Look in the schema, might event be able to use sys.objects and check for a type at the same time.....
Something like
Related
In Snowflake, I retrieve different views with the following SQL query:
SELECT * FROM "myDatabase"."mySchema"."VIEWS"
That returns a table with these columns notably:
TABLE_ID
TABLE_NAME
TABLE_SCHEMA_ID
TABLE_SCHEMA
TABLE_CATALOG_ID
TABLE_CATALOG
TABLE_OWNER
VIEW_DEFINITION
For each VIEW_DEFINITION column entries, I am trying to extract all the strings <Schema_Name>.<View_Name> (or at least the <Schema_Name>).
Is it possible to do that with a SQL query (or by any other way)?
Edit
The table I obtain using the initial query is as follows:
TABLE_ID
TABLE_NAME
TABLE_SCHEMA_ID
TABLE_SCHEMA
TABLE_CATALOG_ID
TABLE_CATALOG
TABLE_OWNER
VIEW_DEFINITION
0001
MY_TABLE_NAME
99
MY_TABLE_SCHEMA
20
PMY_TABLE_CATALOG
MY_OWNER_VIEWS_ADMIN
…
where the VIEW_DEFINITION column contains queries like the one below:
"CREATE OR REPLACE VIEW My_Table_Schema_VIEWS.My_Table_Name AS
WITH STUDY_SITE_SCOPE AS (
SELECT
...
FROM (
SELECT
A.SUBJECT_NUMBER
, A.SUBJECT_STATUS
FROM <Schema_Name>.<View_Name_1> X
JOIN <Schema_Name>.<View_Name_2> Y
...
)
JOIN (
SELECT
...
FROM <Schema_Name>.<View_Name_3> X
JOIN <Schema_Name>.<View_Name_4> Y
...
)
..."
From this VIEW_DEFINITION I am trying to extract all the <Schema_Name>.<View_Name_XX> strings (or at least the <Schema_Name>).
I assume you want to get all base schemas your current view is built on top of.
To answer your question short: Yes, it is.
Maybe the following procedure is giving you an idea on how to solve it via SQL or a Stored Procedure:
Query the view definition
Search for all strings within the view definition that follow the "FROM" or "JOIN" clause
Extract them and probably check for the database name in front of the schema name
You can use information_schema.tables:
select t.*
from information_schema.tables t
where t.table_type = 'VIEW'
I have statement...
SELECT table_name from all_tab_columns;
Which returns...
X
When I attempt...
SELECT * FROM X;
I get...
Table DNE
What is the issue here?
Although your case may be different, in my particular case the issue was that the table X had a different Owner.
To access this, I used the command
SELECT Owner, Table_name FROM all_tab_columns
With the new User information, change your query to
SELECT * FROM Owner.X
Now, you should be able to select said table.
System is HP VERTICA 7.1
I am trying to create a SQL query which will dynamically find all particular tables in a specific schema that have a Timestamp column named DWH_CREATE_TIMESTAMP from system tables. (I have completed this part successfully)
Then, pass this list of tables to an outer query or some kind of looping statement which will select the MAX(DWH_CREATE_TIMESTAMP) and TABLE_NAME from all the tables in the list (200+) and union all the results together into one list.
The expected output is a 2 column table with all said tables with that TS field and the max of each value. Tables are constantly being created and dropped, so the point is to make everything totally dynamic where no TABLE_NAME values are ever hard-coded.
Any idea of Vertica specific ways to accomplish this without UDF's would be greatly appreciated.
Inner Query (working):
select distinct(table_name)
from columns
where column_name = 'DWH_CREATE_TIMESTAMP'
and table_name in (select DISTINCT(table_name) from all_tables where schema_name = 'PTG_DWH')
Outer Query (attempted - not working):
SELECT Max(DWH_CREATE_DATE) from
WITH table_name AS (
select distinct(table_name)
from columns
where column_name = 'DWH_CREATE_DATE' and table_name in (select DISTINCT(table_name) from all_tables where schema_name = 'PTG_DWH'))
SELECT MAX(DWH_CREATE_DATE)
FROM table_name
Thanks!!!
No way to do that in one SQL .
You can used the below method for node max timestamp columns values
select projections.anchor_table_name,vs_ros.colname,max(max_value) from vs_ros,vs_ros_min_max_values,storage_containers,projections where vs_ros.colname ilike 'timestamp'
and vs_ros.salstorageid=storage_containers.sal_storage_id
and vs_ros_min_max_values.rosid=vs_ros.rosid
and storage_containers.projection_name=projections.projection_name
group by projections.anchor_table_name,vs_ros.colname
Is there some SQL that will either return a list of table names or (to cut to the chase) that would return a boolean as to whether a tablename with a certain pattern exists?
Specifically, I need to know if there is a table in the database named INV[Bla] such as INVclay, INVcherri, INVkelvin, INVmorgan, INVgrandFunk, INVgobbledygook, INV2468WhoDoWeAppreciate, etc. (the INV part is what I'm looking for; the remainder of the table name could be almost anything).
IOW, can "wildcards" be used in a SQL statement, such as:
SELECT * tables
FROM database
WHERE tableName = 'INV*'
or how would this be accomplished?
This should get you there:
SELECT *
FROM INFORMATION_SCHEMA.TABLES
where table_name LIKE '%INV%'
EDIT:
fixed table_name
To check for exists:
--
-- note that the sql compiler knows that it just needs to check for existence, so this is a case where "select *" is just fine
if exists
(select *
from [sys].[tables]
where upper([name]) like N'INV%')
select N'do something appropriate because there is a table based on this pattern';
You can try the following:
SELECT name FROM sys.tables where name LIKE 'INV%';
How do i list all tables in a schema in Oracle SQL?
To see all tables in another schema, you need to have one or more of the following system privileges:
SELECT ANY DICTIONARY
(SELECT | INSERT | UPDATE | DELETE) ANY TABLE
or the big-hammer, the DBA role.
With any of those, you can select:
SELECT DISTINCT OWNER, OBJECT_NAME
FROM DBA_OBJECTS
WHERE OBJECT_TYPE = 'TABLE'
AND OWNER = '[some other schema]'
Without those system privileges, you can only see tables you have been granted some level of access to, whether directly or through a role.
SELECT DISTINCT OWNER, OBJECT_NAME
FROM ALL_OBJECTS
WHERE OBJECT_TYPE = 'TABLE'
AND OWNER = '[some other schema]'
Lastly, you can always query the data dictionary for your own tables, as your rights to your tables cannot be revoked (as of 10g):
SELECT DISTINCT OBJECT_NAME
FROM USER_OBJECTS
WHERE OBJECT_TYPE = 'TABLE'
SELECT table_name from all_tables where owner = 'YOURSCHEMA';
You can query USER_TABLES
select TABLE_NAME from user_tables
You can directly run the second query if you know the owner name.
--First you can select what all OWNERS there exist:
SELECT DISTINCT(owner) from SYS.ALL_TABLES;
--Then you can see the tables under by that owner:
SELECT table_name, owner from all_tables where owner like ('%XYZ%');
If you logged in as Normal User without DBA permission you may uses the following command to see your own schema's all tables and views.
select * from tab;
select * from cat;
it will show all tables in your schema cat synonym of user_catalog
If you are accessing Oracle with JDBC (Java) you can use DatabaseMetadata class. If you are accessing Oracle with ADO.NET you can use a similar approach.
If you are accessing Oracle with ODBC, you can use SQLTables function.
Otherwise, if you just need the information in SQLPlus or similar Oracle client, one of the queries already mentioned will do. For instance:
select TABLE_NAME from user_tables
Try this, replace ? with your schema name
select TABLE_NAME from INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA =?
AND TABLE_TYPE = 'BASE TABLE'
select TABLE_NAME from user_tables;
Above query will give you the names of all tables present in that user;
select * from user_tables;
(showing all tables)
SELECT table_name, owner FROM all_tables where owner='schema_name' order by table_name
Name of the table and rows counter for all tables under OWNER schema:
SELECT table_name, num_rows counter from DBA_TABLES WHERE owner = 'OWNER'
Look at my simple utility to show some info about db schema. It is based on: Reverse Engineering a Data Model
Using the Oracle Data Dictionary
If you need to get the size of the table as well, this will be handy:
select SEGMENT_NAME, PARTITION_NAME, BYTES from user_segments where SEGMENT_TYPE='TABLE' order by 1