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T-SQL: Deleting all duplicate rows but keeping one [duplicate]
... I do not care about that. I still need to keep one of these rows however. SELECT DISTINCT won't work because it operates on all columns and I need to suppress duplicates based on the key columns.
...
Get list of all tables in Oracle?
...
SELECT owner, table_name
FROM dba_tables
This is assuming that you have access to the DBA_TABLES data dictionary view. If you do not have those privileges but need them, you can request that the DBA explicitly grants you...
Copy data into another table
...
If both tables are truly the same schema:
INSERT INTO newTable
SELECT * FROM oldTable
Otherwise, you'll have to specify the column names (the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema)...
html select option separator
How do you make a separator in a select tag?
14 Answers
14
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PostgreSQL DISTINCT ON with different ORDER BY
...llowing approaches:
The general solution that should work in most DBMSs:
SELECT t1.* FROM purchases t1
JOIN (
SELECT address_id, max(purchased_at) max_purchased_at
FROM purchases
WHERE product_id = 1
GROUP BY address_id
) t2
ON t1.address_id = t2.address_id AND t1.purchased_at = t2...
What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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What is the equivalent of the C# 'var' keyword in Java?
...), don't forget that non-virtual methods are affected by the Type they are cast as.
I can't imagine a real world scenario where this is indicative of good design, but this may not work as you expect:
class Foo {
public void Non() {}
public virtual void Virt() {}
}
class Bar : Foo {
pu...
Select last row in MySQL
How can I SELECT the last row in a MySQL table?
10 Answers
10
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postgresql: INSERT INTO … (SELECT * …)
...ostgres
CREATE TABLE tblA (id serial, time integer);
INSERT INTO tblA
SELECT id, time
FROM dblink('dbname=dbtest', 'SELECT id, time FROM tblB')
AS t(id integer, time integer)
WHERE time > 1000;
TABLE tblA;
id | time
----+------
1 | 5000
2 | 2000
(2 rows)
PostgreSQL has ...
Search All Fields In All Tables For A Specific Value (Oracle)
...based on
what I think it should be named but it
returned no results.*
SELECT * from dba_objects WHERE
object_name like '%DTN%'
A column isn't an object. If you mean that you expect the column name to be like '%DTN%', the query you want is:
SELECT owner, table_name, column_name FROM all_tab...