Is it possible to display just certain table names in the query:
USE [WebContact]
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'memberEmails'
Most of the time I would need all the table names but there are curtain situations where I need just certain row names.
When I try doing the following:
USE [WebContact]
SELECT COLUMN_NAME, ContactDateTime
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'memberEmails'
It tell me that
Invalid column name 'ContactDateTime'
even though that is one of the row names.
Is this possible to do?
The column ContactDateTime may be a column in your table but it is not a column in the INFORMATION_SCHEMA.COLUMNS view.
Since it is not a column there, SQL Server is going to error out saying that it is invalid.
I think what you're trying to do is add another WHERE clause to your statement:
USE [WebContact]
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'memberEmails'
AND [COLUMN_NAME] = 'ContactDateTime'; -- Here!
Or if you want to add multiple columns...
USE [WebContact]
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'memberEmails'
AND [COLUMN_NAME]
IN ('ContactDateTime', 'column2', 'column3', ... 'column(n)'); -- Here!
Also see here for the case against using INFORMATION_SCHEMAS.
if ContactDateTime is a column that you are looking for in table memberEmails then you can do this
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'memberEmails'
and COLUMN_NAME='ContactDateTime'
The view INFORMATION_SCHEMA.COLUMNS don't have column name ContactDateTime. Please read document first
Related
Good Evening
We have multiple tables in multiple schemas in DB. we are tyring to find out maximum size of each column in the table for all tables and for all schemas.
Example column names: a,b,c,d,e,f,g
Example schema names: A,B,C,D
Expected output:
column_name Max_size_of_column
or
column_name Max_size_of_column column_table table_schema
I have tried the below query, but not able to get the desired output.
SELECT (select column_name from INFORMATION_SCHEMA.COLUMNS
where table_name='building'),
select max(length(select column_name from INFORMATION_SCHEMA.COLUMNS
where table_name='building')) from from INFORMATION_SCHEMA.COLUMNS
where table_name='building'
group by column_name;
Please help us to get the desired output.
Thanks
You need some kind of dynamic SQL for questions like this. But in Postgres this can be done without the need of a PL/pgSQL function, similar to the approach from this answer but combining max() and length():
with all_lengths as (
select table_schema, table_name, column_name,
query_to_xml(format('select max(length(%I)) from %I.%I', column_name, table_schema, table_name), false, true, '') as xml_max
from information_schema.columns
where table_schema in ('public') -- add the schemas you want here
and data_type in ('text', 'character varying')
)
select table_schema, table_name, column_name,
(xpath('/row/max/text()', xml_max))[1]::text::int as max_length
from all_lengths
;
I don't have Postgres 9.5 available, but I think that should work with that old version as well.
If you just want specific columns, rather than all columns with a text or varchar type, then just change the and data_type in (..) condition to and column_name in (...) inside the CTE
I'm Searching for a query to find all possible columns and table names for a specific piece of string/number.
Let's say I have a string/number as 100031-16-FWMD-D20, is there a query to find all the columns and table names which has the value in my database?
Column name-----
Select * from information_schema.columns where column_ name like '%string%'
Table name----
Select * from information_schema.tables where table_name like '%string%'
I would suggest you string up the columns for text datatype from information_schema.columns and after that use the query which is creatd to manually query the search string
Step 1:
select 'select '+column_name+' as search_text,'''+table_name+''' as table_name from '+TABLE_SCHEMA+'.'+TABLE_NAME+' union all'
from INFORMATION_SCHEMA.columns
where TABLE_SCHEMA='dbo'
and data_type like '%char%'
Step 2:
select *
from(<output of Step 1 after removing the last 'union all')x
where x.search_text like '%100031-16-FWMD-D20%'
So I have this:
CREATE PROCEDURE getBattingColumnNames
AS
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'Batting'
AND COLUMN_NAME NOT IN ('playerID','yearID','stint','teamID','lgID', 'G_batting','GIDP','G_old');
GO
And it works great. I get all the column names that I want, in c# I use this to populate a drop down with the column names. however, one of my column names, "Doub" I would like to change. So playing around with it I tried:
SELECT COLUMN_NAME.Doub AS 'DB'
FROM INFORMATION_SCHEMA.COLUMNS
WHERE (TABLE_NAME = 'Batting')
and a variation of that, and the error is the mulitplart identifier could not be bound. How can i change that column name in this query?
You could use a case to translate the column name:
select case COLUMN_NAME
when 'Doub' then 'DB'
else COLUMN_NAME
end
from ...
I wonder if there is a way to find out the default value of some column with a simple select statement. Tried several things like:
SELECT * FROM all_tab_columns WHERE table_name = 'tablename'
But I can't see the defaultvalues for the columns there. And no I do not want to use something like SQL Plus, I need a SELECT, guess there is some table providing that info?
Select TABLE_NAME, COLUMN_NAME, DATA_DEFAULT
from DBA_TAB_COLUMNS
where TABLE_NAME = 'TABLE_NAME';
Replace the Table_Name for which you want to see the default column data.
try the below query
Select * From USER_TAB_COLUMNS where TABLE_NAME ='Table Name'
Default values are in DATA_DEFAULT column from ALL_TAB_COLUMNS:
SELECT TABLE_NAME, COLUMN_NAME, DATA_DEFAULT
FROM ALL_TAB_COLUMNS
WHERE TABLE_NAME = 'tablename'
[2021-01-26] Edit:
Note that the 'tablename' parameter must match the case of real table name, as it appears on ALL_TAB_COLUMNS. More often it will be uppercase, so may be useful use UPPER() function to ensure it.
WHERE TABLE_NAME = UPPER('tablename')
None of the above examples worked for me, but this one did. Key part being the 'Upper' for table_name. Perhaps specific to my team's database but if you're stuck this should work
SELECT a.column_name "Column",
a.data_default "Default"
FROM all_tab_columns a
WHERE a.table_name = Upper('tablename')
I need a query (ORACLE) to pull all the table names and column names in a database for a given value?
Example: If I give a value as "TEST", I need a query which pulls all the TABLE_NAMES and COLUMN_NAMES which has the value "TEST".
select table_name, null column_name from all_tables where table_name like '%TEST%'
union all
select null, column_name from all_tab_columns where column_name like '%TEST%';
Another way is using bind variables within a procedure such
DEFINE vSearch = '%TEST%'
ACCEPT vSearch char PROMPT 'Enter a search value: '
SELECT *
FROM USER_TAB_COLS
WHERE column_name LIKE '&&vSearch'
OR table_name LIKE '&&vSearch';
View All columns of a particular table user use "ALL_TAB_COLUMNS"
If you wants to describe a particular table user use "DESC Table_name;"
Kindly Try this..
You can use the USER_TAB_COLUMNS tables
This should get you columns and tables and views:
SELECT 'Column: '||owner||'.'||table_name||'.'||column_name
FROM dba_tab_columns
WHERE column_name = 'TEST'
UNION ALL
SELECT 'Table: '||owner||'.'||table_name
FROM dba_tables
WHERE table_name = 'TEST'
UNION ALL
SELECT 'View: '||owner||'.'||view_name
FROM dba_views
WHERE view_name = 'TEST';
Note you can also use the ALL_* dictionary views if you don't have access to the DBA_ views, but you'll only see objects you have access to.