Exporting Result Set to Another Table? - sql-server-2005

How can you export a result set given by a query to another table using SQL Server 2005?
I'd like to accomplish this without exporting to CSV?

INSERT INTO TargetTable(Col1, Col2, Col3)
SELECT Col1, Col2, Col3
FROM SourceTable

insert into table(column1, columns, etc) select columns from sourcetable
You can omit column list in insert if columns returned by select matches table definition. Column names in select are ignored, but recommended for readability.
Select into is possible too, but it creates new table. It is sometimes useful for selecting into temporary table, but be aware of tempdb locking by select into.

SELECT col1, col2, ...
INTO dbo.newtable
FROM (SELECT ...query...) AS x;

Related

Copy specific columns from one table to another

I have two tables InventoryOriginal and InventoryBackup. Both had 20 columns, but now InventoryOriginal has changed and has only 12 columns which are common with InventoryBackup. And I need to copy each month's data from InventoryOriginal to InventoryBackup, but it will give me an error because the column number do not match.
I use the simple statement to copy the data which is
INSERT INTO InventoryBackup
Select * from InventoryOriginal where Period = '2020-01-01'
but now the number of columns has changed InventoryOriginal has 12 and InventoryBackup has 20. Can I copy the 12 columns from InventoryOriginal to InventoryBackup and the rest columns can be blank?
getting error - Column name or number of supplied values does not match table definition.
The general way you do this is to mention the target and source columns you want to use. For example, for 3 columns you would use:
INSERT INTO InventoryBackup (col1, col2, col3)
SELECT col1, col2, col3
FROM InventoryOriginal
WHERE Period = '2020-01-01';
Keep in mind that any columns in the target backup table for which were not mentioned would either be assigned a NULL value, or possibly a default value, if the table definition support that.
The simple answer is yes, but you'll likely need to adjust your SQL statement to specify the columns. Eg.
INSERT INTO InventoryBackup (col1, col2, col3, ...)
SELECT col1, col2, col3, ... FROM InventoryOriginal
This will be fine, as long as the extra columns in the "backup" table (that are no longer in the "orignal" table) allow NULLs. If they don't, then you'll need to specify a blank value (or 0, if they're numeric) when you insert. Eg.
INSERT INTO InventoryBackup (col1, col2, col3, extra1, extra2, ...)
SELECT col1, col2, col3, '', 0, ... FROM InventoryOriginal
Hopefully that makes sense. The exact SQL statement that you're going to need is really going to depend on the actual structure of the "backup" table

Avoid Duplicates with INSERT INTO TABLE VALUES from csv file

I have a .csv file with 600 million plus rows. I need to upload this into a database. It will have 3 columns assigned as primary keys.
I use pandas to read the file in chunks of 1000 lines.
At each chunk iteration I use the
INSERT INTO db_name.dbo.table_name("col1", "col2", "col3", "col4")
VALUES (?,?,?,?)
cursor.executemany(query, df.values.tolist())
Syntax with pyodbc in python to upload data in chunks of 1000 lines.
Unfortunately, there are apparently some duplicate rows present. When the duplicate row is encountered the uploading stops with an error from SQL Server.
Question: how can I upload data such that whenever a duplicate is encountered instead of stopping it will just skip that line and upload the rest? I found some questions and answers on insert into table from another table, or insert into table from variables declared, but nothing on reading from a file and using insert into table col_names values() command.
Based on those answers one idea might be:
At each iteration of chunks:
Upload to a temp table
Do the insertion from the temp table into the final table
Delete the rows in the temp table
However, with such a large file each second counts, and I was looking for an answer with better efficiency.
I also tried to deal with duplicates using python, however, since the file is too large to fit into the memory I could not find a way to do that.
Question 2: if I were to use bulk insert, how would I achieve to skip over the duplicates?
Thank you
You can try to use a CTE and an INSERT ... SELECT ... WHERE NOT EXISTS.
WITH cte
AS
(
SELECT ? col1,
? col2,
? col3,
? col4
)
INSERT INTO db_name.dbo.table_name
(col1,
col2,
col3,
col4)
SELECT col1,
col2,
col3,
col4
FROM cte
WHERE NOT EXISTS (SELECT *
FROM db_name.dbo.table_name
WHERE table_name.col1 = cte.col1
AND table_name.col2 = cte.col2
AND table_name.col3 = cte.col3
AND table_name.col4 = cte.col4);
Possibly delete some of the table_name.col<n> = cte.col<n>, if the column isn't part of the primary key.
I would always load into a temporary load table first, which doesn't have any unique or PK constraint on those columns. This way you can always see that the whole file has loaded, which is an invaluable check in any ETL work, and for any other easy analysis of the source data.
After that then use an insert such as suggested by an earlier answer, or if you know that the target table is empty then simply
INSERT INTO db_name.dbo.table_name(col1,col2,col3,col4)
SELECT distinct col1,col2,col3,col4 from load_table
The best approach is to use a temporary table and execute a MERGE-INSERT statement. You can do something like this (not tested):
CREATE TABLE #MyTempTable (col1 VARCHAR(50), col2, col3...);
INSERT INTO #MyTempTable(col1, col2, col3, col4)
VALUES (?,?,?,?)
CREATE CLUSTERED INDEX ix_tempCol1 ON #MyTempTable (col1);
MERGE INTO db_name.dbo.table_name AS TARGET
USING #MyTempTable AS SOURCE ON TARGET.COL1 = SOURCE.COL1 AND TARGET.COL2 = SOURCE.COL2 ...
WHEN NOT MATCHED THEN
INSERT(col1, col2, col3, col4)
VALUES(source.col1, source.col2, source.col3, source.col4);
You need to consider the best indexes for your temporary table to make the MERGE faster. With the statement WHEN NOT MATCHED you avoid duplicates depending on the ON clause.
SQL Server Integration Services offers one method that can read data from a source (via a Dataflow task), then remove duplicates using it's Sort control (a checkbox to remove duplicates).
https://www.mssqltips.com/sqlservertip/3036/removing-duplicates-rows-with-ssis-sort-transformation/
Of course the data has to be sorted and 60 million+ rows isn't going to be fast.
If you want to use pure SQL Server then you need a staging table (without a pk constraint). After importing your data into Staging, you would insert into your target table using filtering for the composite PK combination. For example,
Insert into dbo.RealTable (KeyCol1, KeyCol2, KeyCol3, Col4)
Select Col1, Col2, Col3, Col4
from dbo.Staging S
where not exists (Select *
from dbo.RealTable RT
where RT.KeyCol1 = S.Col1
AND RT.KeyCol2 = S.Col2
AND RT.KeyCol3 = S.Col3
)
In theory you could also use the set operator EXCEPT since it takes the distinct values from both tables. For example:
INSERT INTO RealTable
SELECT * FROM Staging
EXCEPT
SELECT * FROM RealTable
Would insert distinct rows from Staging into RealTable (that don't already exist in RealTable). This method doesn't take into account the composite PK using different values on multiple rows- so an insert error would indicate different values are being assigned to the same PK composite key in the csv.

Insert with select statement gives error Only one expression in select without exists

I am new to SQL Server and have a problem with an insert statement. I am to convert an old database to a SQL server relational database. I am transferring the old data into new tables. The old records are not complete which is causing problems because the fields in the new tables do not allow null values. So what I am trying to do is in insert n/a in the missing fields and then use the select statement to retrieve the available data from the old table all at the same time so I don't get null value not allowed, but I get the error Only one expression can be specified in the select list when the subquery is not introduced with EXISTS along with the Insert statement has more columns than the values statement.
I sure there is a way to do this but I can't figure it out, hope someone can help. Below is an abbreviated description to the statement.
insert into database1.dbo.table (col1, col2, .....col10)
values('n/a','n/a',(select col3, col4...col10 from database2.dbo.table)
You can try to use INSERT INTO ... SELECT
INSERT INTO database1.dbo.table (col1, col2, .....col10)
SELECT 'n/a',
'n/a',
col3,
col4,
...col10
FROM database2.dbo.table

Rename a single column while using select * in oracle

I am selecting all column of my table (eg 40 columns) and i want to rename only one column (e.g col20 ). how can i rename this column in my select query while selecting all column using select *. I don't want to write the name of all column. one more thing i also don't want to change the order of column in my table
Short answer is, you can't.
Either you have to select all the columns individually, using
select col1, col2, col3, ..., col20 as NewCol, ...., col40 from table
or use
select * from table
You can't have both.
Another option is there which you can use like below, but this will add an extra column in the output.
select t.*, t.col20 as NewCol from table t

Need SQL help - How can I select rows to perform an insert?

I tried to make the title as clear as possible... here is my scenario:
I have 2 tables (let's call them table A and table B) that have a similar schema. I would like write a stored procedure that would select specific columns of data out of table A, and insert this data as a new record in table B.
Can someone point me in the write direction to make such a query? I am unsure how to "Hold" the values from the first query, so that I may then perform the insert.
I am trying to avoid making a query, processing it with C# and then making another query...
Thanks.
INSERT INTO B (Col1, Col2) SELECT Col1, Col2 FROM A
Is this what you mean?
You can do this as a single query from C# like this:
Insert into tableB (col1, col2, col3) select col1, col2, col3 from tableA where ...
The trick is that column names need to be in the same order and compatible types.
use a SELECT INTO
SELECT
[Col1],
[COl2]
INTO TableA
FROM TableB