I have two identical tables and need to copy rows from table to another. What is the best way to do that? (I need to programmatically copy just a few rows, I don't need to use the bulk copy utility).
As long as there are no identity columns you can just
INSERT INTO TableNew
SELECT * FROM TableOld
WHERE [Conditions]
Alternative syntax:
INSERT tbl (Col1, Col2, ..., ColN)
SELECT Col1, Col2, ..., ColN
FROM Tbl2
WHERE ...
The select query can (of course) include expressions, case statements, constants/literals, etc.
Jarrett's answer creates a new table.
Scott's answer inserts into an existing table with the same structure.
You can also insert into a table with different structure:
INSERT Table2
(columnX, columnY)
SELECT column1, column2 FROM Table1
WHERE [Conditions]
SELECT * INTO < new_table > FROM < existing_table > WHERE < clause >
INSERT INTO DestTable
SELECT * FROM SourceTable
WHERE ...
works in SQL Server
To select only few rows..This will work like charm..
SELECT TOP 10 *
INTO db2.dbo.new_table
FROM db1.dbo.old_table;
Note : Just create a new table in the required db..We need not define its structure.
Related
So for each distinct value in a column of one table I want to insert that unique value into a row of another table.
list = select distinct(id) from table0
for distinct_id in list
insert into table1 (id) values (distinct_id)
end
Any ideas as to how to go about this?
Whenever you think about doing something in a loop, step back, and think again. SQL is optimized to work with sets. You can do this using a set-based query without the need to loop:
INSERT dbo.table1(id) SELECT DISTINCT id FROM dbo.table0;
There are some edge cases where looping can make more sense, but as SQL Server matures and more functionality is added, those edge cases get narrower and narrower...
insert into table1 (id)
select distinct id from table0
The following statement works with me.
insert into table1(col1, col2) select distinct on (col1) col1 col2 from table0
The below query will also check the existing data in the Table2.
INSERT INTO Table2(Id) SELECT DISTINCT Id FROM Table1 WHERE Id NOT IN(SELECT Id FROM Table2);
Other Simple way to copy distinct data with multiple columns from one table to other
Insert into TBL2
Select * from (Select COL1, ROW_NUMBER() over(PARTITION BY COL1 Order By COL1) AS COL2 From TBL1)T
where T.COL2 = 1
How to copy/append data from one table into another table with same schema in SQL Server?
Edit:
let's say there is a query
select *
into table1
from table2
where 1=1
which creates table1 with the same schema as well as data as in table2.
Is there any short query like this to only copy entire data only into an already existing 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):
INSERT INTO newTable (col1, col2, col3)
SELECT column1, column2, column3
FROM oldTable
Simple way if new table does not exist and you want to make a copy of old table with everything then following works in SQL Server.
SELECT * INTO NewTable FROM OldTable
This is the proper way to do it:
INSERT INTO destinationTable
SELECT * FROM sourceTable
INSERT INTO table1 (col1, col2, col3)
SELECT column1, column2, column3
FROM table2
Try this:
INSERT INTO MyTable1 (Col1, Col2, Col4)
SELECT Col1, Col2, Col3 FROM MyTable2
Try this:
Insert Into table2
Select * from table1
Insert Selected column with condition
INSERT INTO where_to_insert (col_1,col_2) SELECT col1, col2 FROM from_table WHERE condition;
Copy all data from one table to another with the same column name.
INSERT INTO where_to_insert
SELECT * FROM from_table WHERE condition;
INSERT INTO DestinationTable(SupplierName, Country)
SELECT SupplierName, Country FROM SourceTable;
It is not mandatory column names to be same.
CREATE TABLE `table2` LIKE `table1`;
INSERT INTO `table2` SELECT * FROM `table1`;
the first query will create the structure from table1 to table2 and second query will put the data from table1 to table2
Copy all columns from one table to another table:
INSERT INTO table2
SELECT * FROM table1
WHERE condition;
Copy only some columns from one table into another table:
INSERT INTO table2 (column1, column2, column3, ...)
SELECT column1, column2, column3, ...
FROM table1
WHERE condition;
You can duplicate or "clone" a table's contents by executing:
CREATE TABLE new_table AS SELECT * FROM original_table;
-- for Sql Server users.
if you don't have the new table then you can create the new table with same structure as old table, and also copy data over from old table to the new table. For example:
select * into new_table
from old_table;
also you can copy the column / table structure, and just some of data. For example:
select * into new_table
from old_table
where country = 'DE';
I am selecting multiple rows and inserting them into another table. I want to make sure that it doesn't already exists in the table I am inserting multiple rows into.
DISTINCT works when there are duplicate rows in the select, but not when comparing it to the data already in the table your inserting into.
If I Selected one row at a time I could do a IF EXIST but since its multiple rows (sometimes 10+) it doesn't seem like I can do that.
INSERT INTO target_table (col1, col2, col3)
SELECT DISTINCT st.col1, st.col2, st.col3
FROM source_table st
WHERE NOT EXISTS (SELECT 1
FROM target_table t2
WHERE t2.col1 = st.col1
AND t2.col2 = st.col2
AND t2.col3 = st.col3)
If the distinct should only be on certain columns (e.g. col1, col2) but you need to insert all column, you will probably need some derived table (ANSI SQL):
INSERT INTO target_table (col1, col2, col3)
SELECT st.col1, st.col2, st.col3
FROM (
SELECT col1,
col2,
col3,
row_number() over (partition by col1, col2 order by col1, col2) as rn
FROM source_table
) st
WHERE st.rn = 1
AND NOT EXISTS (SELECT 1
FROM target_table t2
WHERE t2.col1 = st.col1
AND t2.col2 = st.col2)
If you already have a unique index on whatever fields need to be unique in the destination table, you can just use INSERT IGNORE (here's the official documentation - the relevant bit is toward the end), and have MySQL throw away the duplicates for you.
Hope this helps!
So you're looking to retrieve all unique rows from source table which do not already exist in target table?
SELECT DISTINCT(*) FROM source
WHERE primaryKey NOT IN (SELECT primaryKey FROM target)
That's assuming you have a primary key which you can base the uniqueness on... otherwise, you'll have to check each column for uniqueness.
pseudo code for what might work
insert into <target_table> select col1 etc
from <source_table>
where <target_table>.keycol not in
(select source_table.keycol from source_table)
There are a few MSDN articles out there about this, but by far this one is the best:
http://msdn.microsoft.com/en-us/library/ms162773.aspx
They made it real easy to implement and my problem is now fixed. Also the GUI is ugly, but you actually can set minute intervals without using the command line in windows 2003.
I have two tables with the same structure. I need to select data from one table and have to store them into the other.
How can I do that?
insert into tablea(id,name) select id,name from tableb;
Since they are the same structure then you can just do
insert into table1 select colum1, column2,... from table2
insert into blacklist
select *
from newblacklist
for uploading any single number
insert into blacklist
select *
from newblacklist
where numbers ='123456'
leave out the values keyword
insert into tbl1
select * from tbl2
I have a table with say 3 columns. There's no primary key so there can be duplicate rows. I need to just keep one and delete the others. Any idea how to do this is Sql Server?
I'd SELECT DISTINCT the rows and throw them into a temporary table, then drop the source table and copy back the data from the temp.
EDIT: now with code snippet!
INSERT INTO TABLE_2
SELECT DISTINCT * FROM TABLE_1
GO
DELETE FROM TABLE_1
GO
INSERT INTO TABLE_1
SELECT * FROM TABLE_2
GO
Add an identity column to act as a surrogate primary key, and use this to identify two of the three rows to be deleted.
I would consider leaving the identity column in place afterwards, or if this is some kind of link table, create a compound primary key on the other columns.
The following example works as well when your PK is just a subset of all table columns.
(Note: I like the approach with inserting another surrogate id column more. But maybe this solution comes handy as well.)
First find the duplicate rows:
SELECT col1, col2, count(*)
FROM t1
GROUP BY col1, col2
HAVING count(*) > 1
If there are only few, you can delete them manually:
set rowcount 1
delete from t1
where col1=1 and col2=1
The value of "rowcount" should be n-1 times the number of duplicates. In this example there are 2 dulpicates, therefore rowcount is 1. If you get several duplicate rows, you have to do this for every unique primary key.
If you have many duplicates, then copy every key once into anoher table:
SELECT col1, col2, col3=count(*)
INTO holdkey
FROM t1
GROUP BY col1, col2
HAVING count(*) > 1
Then copy the keys, but eliminate the duplicates.
SELECT DISTINCT t1.*
INTO holddups
FROM t1, holdkey
WHERE t1.col1 = holdkey.col1
AND t1.col2 = holdkey.col2
In your keys you have now unique keys. Check if you don't get any result:
SELECT col1, col2, count(*)
FROM holddups
GROUP BY col1, col2
Delete the duplicates from the original table:
DELETE t1
FROM t1, holdkey
WHERE t1.col1 = holdkey.col1
AND t1.col2 = holdkey.col2
Insert the original rows:
INSERT t1 SELECT * FROM holddups
btw and for completeness: In Oracle there is a hidden field you could use (rowid):
DELETE FROM our_table
WHERE rowid not in
(SELECT MIN(rowid)
FROM our_table
GROUP BY column1, column2, column3... ;
see: Microsoft Knowledge Site
Here's the method I used when I asked this question -
DELETE MyTable
FROM MyTable
LEFT OUTER JOIN (
SELECT MIN(RowId) as RowId, Col1, Col2, Col3
FROM MyTable
GROUP BY Col1, Col2, Col3
) as KeepRows ON
MyTable.RowId = KeepRows.RowId
WHERE
KeepRows.RowId IS NULL
This is a way to do it with Common Table Expressions, CTE. It involves no loops, no new columns or anything and won't cause any unwanted triggers to fire (due to deletes+inserts).
Inspired by this article.
CREATE TABLE #temp (i INT)
INSERT INTO #temp VALUES (1)
INSERT INTO #temp VALUES (1)
INSERT INTO #temp VALUES (2)
INSERT INTO #temp VALUES (3)
INSERT INTO #temp VALUES (3)
INSERT INTO #temp VALUES (4)
SELECT * FROM #temp
;
WITH [#temp+rowid] AS
(SELECT ROW_NUMBER() OVER (ORDER BY i ASC) AS ROWID, * FROM #temp)
DELETE FROM [#temp+rowid] WHERE rowid IN
(SELECT MIN(rowid) FROM [#temp+rowid] GROUP BY i HAVING COUNT(*) > 1)
SELECT * FROM #temp
DROP TABLE #temp
This is a tough situation to be in. Without knowing your particular situation (table size etc) I think that your best shot is to add an identity column, populate it and then delete according to it. You may remove the column later but I would suggest that you should keep it as it is really a good thing to have in the table
After you clean up the current mess you could add a primary key that includes all the fields in the table. that will keep you from getting into the mess again.
Of course this solution could very well break existing code. That will have to be handled as well.
Can you add a primary key identity field to the table?
Manrico Corazzi - I specialize in Oracle, not MS SQL, so you'll have to tell me if this is possible as a performance boost:-
Leave the same as your first step - insert distinct values into TABLE2 from TABLE1.
Drop TABLE1. (Drop should be faster than delete I assume, much as truncate is faster than delete).
Rename TABLE2 as TABLE1 (saves you time, as you're renaming an object rather than copying data from one table to another).
Here's another way, with test data
create table #table1 (colWithDupes1 int, colWithDupes2 int)
insert into #table1
(colWithDupes1, colWithDupes2)
Select 1, 2 union all
Select 1, 2 union all
Select 2, 2 union all
Select 3, 4 union all
Select 3, 4 union all
Select 3, 4 union all
Select 4, 2 union all
Select 4, 2
select * from #table1
set rowcount 1
select 1
while ##rowcount > 0
delete #table1 where 1 < (select count(*) from #table1 a2
where #table1.colWithDupes1 = a2.colWithDupes1
and #table1.colWithDupes2 = a2.colWithDupes2
)
set rowcount 0
select * from #table1
What about this solution :
First you execute the following query :
select 'set rowcount ' + convert(varchar,COUNT(*)-1) + ' delete from MyTable where field=''' + field +'''' + ' set rowcount 0' from mytable group by field having COUNT(*)>1
And then you just have to execute the returned result set
set rowcount 3 delete from Mytable where field='foo' set rowcount 0
....
....
set rowcount 5 delete from Mytable where field='bar' set rowcount 0
I've handled the case when you've got only one column, but it's pretty easy to adapt the same approach tomore than one column. Let me know if you want me to post the code.
How about:
select distinct * into #t from duplicates_tbl
truncate duplicates_tbl
insert duplicates_tbl select * from #t
drop table #t
I'm not sure if this works with DELETE statements, but this is a way to find duplicate rows:
SELECT *
FROM myTable t1, myTable t2
WHERE t1.field = t2.field AND t1.id > t2.id
I'm not sure if you can just change the "SELECT" to a "DELETE" (someone wanna let me know?), but even if you can't, you could just make it into a subquery.