I am inserting only new records that do not exist in a live table from a "dump" table. My issue is there is an identity column that I don't want to insert into the live, I want the live tables identity column to take care of incrementing the value but I am getting an insert error "Insert Error: Column name or number of supplied values does not match table definition." Is there a way around this or is the only fix to remove the identity column all together?
Thanks,
Sam
You need to list of all the needed columns in your query, excluding the identity column.
One more reason why you should never use SELECT *.
INSERT liveTable
(col1, col2, col3)
SELECT col1, col2, col3
FROM dumpTable dt
WHERE NOT EXISTS
(
SELECT 1
FROM liveTable lt
WHERE lt.Id == dt.Id
)
Pro tip: You can also achieve the above by using an OUTER JOIN between the dump and live tables and using WHERE liveTable.col1 = NULL (you will probably need to qualify the column names selected with the dump table alias).
I figured out the issue.... my live table didn't have the ID field set as an identity, somehow when I created it that field wasn't set up correctly.
you can leave that column in your insert statment like this
insert into destination (col2, col3, col4)
select col2, col3 col4 from source
Don't do just
insert into destination
select * from source
Related
For a first time I find very handy way for importing "last year data" to "this year data".
This works well:
DROP TABLE IF EXISTS mytable;
CREATE TABLE mytable AS
SELECT col1, col2, col3, col4
FROM dblink('host=localhost port=xxxx user=xxxx password=xxxx dbname=mylastyeardb',
'SELECT col1, col2, col3, col4
FROM mytable
WHERE TRIM(col1)<>'''' ')
AS x(col1 text, col2 text, col3 text, col4 text);
ALTER TABLE mytable ADD COLUMN cols_id SERIAL PRIMARY KEY;
Since 'cols_id' from old table is not appropriate for a new table maybe some of experienced users know how to setup a table in CREATE TABLE AS that it have 'cols_id' as (serial) primary key nice ordered and as a first column. Maybe such way I can avoid using of second (ALTER) command?
Any other advice for showed situation will be welcome too.
you either create table, defining its structure (with all handy shortcuts and options in one statement), or create table as select, "inheriting" [partially] the structure. Thus if you want primary key, you will need alter tabale any way...
To put id as first column in one statement, you can simply use a dummy value, eg sequential number:
t=# create table s as select row_number() over() as id,chr(n) from generate_series(197,200) n;
SELECT 4
t=# select * from s;
id | chr
----+-----
1 | Å
2 | Æ
3 | Ç
4 | È
(4 rows)
Of course after that you still need to create sequence, assign its value as default to the id column and add primary key on ot. Which makes it even more statements then you have ATM...
Is there a way in db2 where I can replace the entire table with just selected rows from the same table ?
Something like REPLACE into tableName select * from tableName where col1='a';
(I can export the selected rows, delete the entire table and load/import again, but I want to avoid these steps and use a single query).
Original table
col1 col2
a 0 <-- replace all rows and replace with just col1 = 'a'
a 1 <-- col1='a'
b 2
c 3
Desired resultant table
col1 col2
a 0
a 1
Any help appreciated !
Thanks.
This is a duplicate of my answer to your duplicate question:
You can't do this in a single step. The locking required to truncate the table precludes you querying the table at the same time.
The best option you would have is to declare a global temporary table (DGTT) and insert the rows you want into it, truncate the source table, and then insert the rows from the DGTT back into the source table. Something like:
declare global temporary table t1
as (select * from schema.tableName where ...)
with no data
on commit preserve rows
not logged;
insert into session.t1 select * from schema.tableName;
truncate table schema.tableName immediate;
insert into schema.tableName select * from session.t1;
I know of no way to do what you're asking in one step...
You'd have to select out to a temporary table then copy back.
But I don't understand why you'd need to do this in the first place. Lets assume there was a REPLACE TABLE command...
REPLACE TABLE mytbl WITH (
SELECT * FROM mytbl
WHERE col1 = 'a' AND <...>
)
Why not simply delete the inverse set of rows...
DELETE FROM mytbl
WHERE NOT (col1 = 'a' AND <...>)
Note the comparisons done in the WHERE clause are the exact same. You just wrap them in a NOT ( ) to delete the ones you don't want to keep.
Is it possible to SELECT * but without n-th column, for example 2nd?
I have some view that have 4 and 5 columns (each has different column names, except for the 2nd column), but I do not want to show the second column.
SELECT * -- how to prevent 2nd column to be selected?
FROM view4
WHERE col2 = 'foo';
SELECT * -- how to prevent 2nd column to be selected?
FROM view5
WHERE col2 = 'foo';
without having to list all the columns (since they all have different column name).
The real answer is that you just can not practically (See LINK). This has been a requested feature for decades and the developers refuse to implement it. The best practice is to mention the column names instead of *. Using * in itself a source of performance penalties though.
However, in case you really need to use it, you might need to select the columns directly from the schema -> check LINK. Or as the below example using two PostgreSQL built-in functions: ARRAY and ARRAY_TO_STRING. The first one transforms a query result into an array, and the second one concatenates array components into a string. List components separator can be specified with the second parameter of the ARRAY_TO_STRING function;
SELECT 'SELECT ' ||
ARRAY_TO_STRING(ARRAY(SELECT COLUMN_NAME::VARCHAR(50)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME='view4' AND
COLUMN_NAME NOT IN ('col2')
ORDER BY ORDINAL_POSITION
), ', ') || ' FROM view4';
where strings are concatenated with the standard operator ||. The COLUMN_NAME data type is information_schema.sql_identifier. This data type requires explicit conversion to CHAR/VARCHAR data type.
But that is not recommended as well, What if you add more columns in the long run but they are not necessarily required for that query?
You would start pulling more column than you need.
What if the select is part of an insert as in
Insert into tableA (col1, col2, col3.. coln) Select everything but 2 columns FROM tableB
The column match will be wrong and your insert will fail.
It's possible but I still recommend writing every needed column for every select written even if nearly every column is required.
Conclusion:
Since you are already using a VIEW, the simplest and most reliable way is to alter you view and mention the column names, excluding your 2nd column..
-- my table with 2 rows and 4 columns
DROP TABLE IF EXISTS t_target_table;
CREATE TEMP TABLE t_target_table as
SELECT 1 as id, 1 as v1 ,2 as v2,3 as v3,4 as v4
UNION ALL
SELECT 2 as id, 5 as v1 ,-6 as v2,7 as v3,8 as v4
;
-- my computation and stuff that i have to messure, any logic could be done here !
DROP TABLE IF EXISTS t_processing;
CREATE TEMP TABLE t_processing as
SELECT *, md5(t_target_table::text) as row_hash, case when v2 < 0 THEN true else false end as has_negative_value_in_v2
FROM t_target_table
;
-- now we want to insert that stuff into the t_target_table
-- this is standard
-- INSERT INTO t_target_table (id, v1, v2, v3, v4) SELECT id, v1, v2, v3, v4 FROM t_processing;
-- this is andvanced ;-)
INSERT INTO t_target_table
-- the following row select only the columns that are pressent in the target table, and ignore the others.
SELECT r.* FROM (SELECT to_jsonb(t_processing) as d FROM t_processing) t JOIN LATERAL jsonb_populate_record(NULL::t_target_table, d) as r ON TRUE
;
-- WARNING : you need a object that represent the target structure, an exclusion of a single column is not possible
For columns col1, col2, col3 and col4 you will need to request
SELECT col1, col3, col4 FROM...
to omit the second column. Requesting
SELECT *
will get you all the columns
I am using SQL Server where I have designed a view to sum the results of two tables and I want the output to be a single table with the results. My query simplified is something like:
SELECT SUM(col1), col2, col3
FROM Table1
GROUP BY col2, col3
This gives me the data I want, but when updating my EDM the view is excluded because "a primary key cannot be inferred".
With a little research I modified the query to spoof an id column to as follows:
SELECT ROW_NUMBER() OVER (ORDER BY col2) AS 'ID', SUM(col1), col2, col3
FROM Table1
GROUP BY col2, col3
This kind of query gives me a nice increasing set of ids. However, when I attempt to update my model it still excludes my view because it cannot infer a primary key. How can we use views that aggregate records and connect them with Linq-to-Entities?
As already discussed in the comments you can try adding MAX(id) as id to the view. Based on your feedback this would become:
SELECT ISNULL(MAX(id), 0) as ID,
SUM(col1),
col2,
col3
FROM Table1
GROUP BY col2, col3
Another option is to try creating an index on the view:
CREATE UNIQUE CLUSTERED INDEX idx_view1 ON dbo.View1(id)
I use this code alter view
ISNULL(ROW_NUMBER() OVER(ORDER BY ActionDate DESC), -1) AS RowID
I use this clause in multi relations view / table query
ROW_NUMBER never give null value because it never seen -1
This is all I needed to add in order to import my view into EF6.
select ISNULL(1, 1) keyField
What I'm trying to do is select various rows from a certain table and insert them right back into the same table. My problem is that I keep running into the whole "duplicate PK" error - is there a way to skip the PK field when executing an INSERT INTO statement in PostgreSQL?
For example:
INSERT INTO reviews SELECT * FROM reviews WHERE rev_id=14;
the rev_id in the preceding SQL is the PK key, which I somehow need to skip. (To clarify: I am using * in the SELECT statement because the number of table columns can increase dynamically).
So finally, is there any way to skip the PK field?
Thanks in advance.
You can insert only the values you want so your PK will get auto-incremented
insert into reviews (col1, col2, col3) select col1, col2, col3 from reviews where rev_id=14
Please do not retrieve/insert the id-column
insert into reviews (col0, col1, ...) select col0, col1, ... from reviews where rev_id=14;