I have a table with 2 columns like this
COLNUM | COLSTR
---------------
1 | 001223
2 | 002234
3 | ds2-dd
4 | 003344
I would like to make query like this
SELECT * FROM TABLE WHERE CAST(COLSTR AS NUMBER) IN (1223,3344)
But since 4th row can not cast to number, query fails. I could create a view which would eliminate non-number-transformable rows, but I would like to make this with one query. How do I do it?
Oracle 11g.
Thanks.
I would suggest to use regular expression
SELECT * FROM TABLE WHERE REGEXP_LIKE(COLSTR,'^[0-9]$')
Related
I have to sync two databases. The first one (source) run on Sybase and the second (dist) run on PostgreSQL. I make for each rows a comparaison to check if the row exist or not (comparaison of the pk). But, for a specific table, the pk is a varchar.
I make :
SELECT * FROM table ORDER BY 1;
The table output look like this on Sybase :
# | row 1
.. | row 2
1 | row 3
...
and on PostgreSQL :
.. | row 1
# | row 2
1 | row 3
So, the rows have not the same order. I would like to obtain the same output in PostgreSQL that my Sybase db (SQL Anywhere).
Any idea ?
If I understand you correctly you need this query :
WITH x(a) AS (SELECT * FROM table ORDER BY 1)
SELECT *
FROM x
ORDER BY a COLLATE "C";
Suppose there is a table which has several identical rows. I can copy the distinct values by
SELECT DISTINCT * INTO DESTINATIONTABLE FROM SOURCETABLE
but if the table has a column named value and for the sake of simplicity its value is 1 for one particular item in that table. Now that row has another 9 duplicates. So the summation of the value column for that particular item is 10. Now I want to remove the 9 duplicates(or copy the distinct value as I mentioned) and for that item now the value should show 10 and not 1. How can this be achieved?
item| value
----+----------------
A | 1
A | 1
A | 1
A | 1
B | 1
B | 1
I want to show this as below
item| value
----+----------------
A | 4
B | 2
Thanks in advance
You can try to use SUM and group by
SELECT item,SUM(value) value
FROM T
GROUP BY item
SQLfiddle:http://sqlfiddle.com/#!18/fac26/1
[Results]:
| item | value |
|------|-------|
| A | 4 |
| B | 2 |
Broadly speaking, you can just us a sum and a GROUP BY clause.
Something like:
SELECT column1, SUM(column2) AS Count
FROM SOURCETABLE
GROUP BY column1
Here it is in action: Sum + Group By
Since your table probably isn't just two columns of data, here is a slightly more complex example showing how to do this to a larger table: SQL Fiddle
Note that I've selected my rows individually so that I can access the necessary data, rather than using
SELECT *
And I have achieved this result without the need for selecting data into another table.
EDIT 2:
Further to your comments, it sounds like you want to alter the actual data in your table rather than just querying it. There may be a more elegant way to do this, but a simple way use the above query to populate a temporary table, delete the contents of the existing table, then move all the data back. To do this in my existing example:
WITH MyQuery AS (
SELECT name, type, colour, price, SUM(number) AS number
FROM MyTable
GROUP BY name, type, colour, price
)
SELECT * INTO MyTable2 FROM MyQuery;
DELETE FROM MyTable;
INSERT INTO MyTable(name, type, colour, price, number)
SELECT * FROM MyTable2;
DROP TABLE MyTable2;
WARNING: If youre going to try this, please use a development environment first (i.e one you don't mind breaking!) to ensure it does exactly what you want it to do. It's imperative that your initial query captures ALL the data you want.
Here is the SQL Fiddle of this example in action: SQL Fiddle
Table data sample:
--------------------------
| key | domain | value |
--------------------------
| a | en | English |
| a | de | Germany |
Query which returns result I need:
select * from
(
select t1.key,
(select value from TABLE where t1.key=key AND code='en') en,
(select value from TABLE where t1.key=key AND code='de') de
from TABLE t1
) as t2
Data returned from query:
---------------------------
| key | en | de |
---------------------------
| a | English | Germany |
I do not want to list all available domains with:
(select value from TABLE where t1.key=key AND code='*') *
Is it possible to make this query more dynamic in Postgres: automatically add all domain columns that exist in the table?
For more than a few domains use crosstab() to make the query shorter and faster.
PostgreSQL Crosstab Query
A completely dynamic query, returning a dynamic number of columns based on data in your table is not possible, because SQL is strictly typed. Whatever you try, you'll end up needing two steps. Step 1: generate the query, step 2: execute it.
Execute a dynamic crosstab query
Or you return something more flexible instead of table columns, like an array or a document type like json. Details:
Dynamic alternative to pivot with CASE and GROUP BY
Refactor a PL/pgSQL function to return the output of various SELECT queries
Using Oracle 10G
Say for example I have a table with three fields in it, I'd like one query which selects the counts of each column where they are not null. Field name
----------------------------------
| strTest1 | strTest2 | strTest3 |
----------------------------------
I know how to get the count of each one individually:
select count(*) from tablename where strTest1 is not null
but I'd like to know if it's possible to do this within one query for all 3 fields.
Thanks
It sounds like you want:
SELECT COUNT(STRTEST1), COUNT(STRTEST2), COUNT(STRTEST3) FROM YOUR_TABLE
This is staight forward I believe:
I have a table with 30,000 rows. When I SELECT DISTINCT 'location' FROM myTable it returns 21,000 rows, about what I'd expect, but it only returns that one column.
What I want is to move those to a new table, but the whole row for each match.
My best guess is something like SELECT * from (SELECT DISTINCT 'location' FROM myTable) or something like that, but it says I have a vague syntax error.
Is there a good way to grab the rest of each DISTINCT row and move it to a new table all in one go?
SELECT * FROM myTable GROUP BY `location`
or if you want to move to another table
CREATE TABLE foo AS SELECT * FROM myTable GROUP BY `location`
Distinct means for the entire row returned. So you can simply use
SELECT DISTINCT * FROM myTable GROUP BY 'location'
Using Distinct on a single column doesn't make a lot of sense. Let's say I have the following simple set
-id- -location-
1 store
2 store
3 home
if there were some sort of query that returned all columns, but just distinct on location, which row would be returned? 1 or 2? Should it just pick one at random? Because of this, DISTINCT works for all columns in the result set returned.
Well, first you need to decide what you really want returned.
The problem is that, presumably, for some of the location values in your table there are different values in the other columns even when the location value is the same:
Location OtherCol StillOtherCol
Place1 1 Fred
Place1 89 Fred
Place1 1 Joe
In that case, which of the three rows do you want to select? When you talk about a DISTINCT Location, you're condensing those three rows of different data into a single row, there's no meaning to moving the original rows from the original table into a new table since those original rows no longer exist in your DISTINCT result set. (If all the other columns are always the same for a given Location, your problem is easier: Just SELECT DISTINCT * FROM YourTable).
If you don't care which values come from the other columns you can use a (bad, IMHO) MySQL extension to SQL and do:
SELECT * FROM YourTable GROUP BY Location
which will give a result set with one row per location and values for the other columns derived from the original data in an undefined fashion.
Multiple rows with identical values in all columns don't have any sense. OK - the question might be a way to correct exactly that situation.
Considering this table, with id being the PK:
kram=# select * from foba;
id | no | name
----+----+---------------
2 | 1 | a
3 | 1 | b
4 | 2 | c
5 | 2 | a,b,c,d,e,f,g
you may extract a sample for every single no (:=location) by grouping over that column, and selecting the row with minimum PK (for example):
SELECT * FROM foba WHERE id IN (SELECT min (id) FROM foba GROUP BY no);
id | no | name
----+----+------
2 | 1 | a
4 | 2 | c