I have two tables:
CREATE TABLE public.test
(
id integer NOT NULL GENERATED ALWAYS AS IDENTITY
)
and
CREATE TABLE public.test2
(
id integer,
test_id integer
)
Table test2 has two rows (1, null) and (2, null). Table test has nothing. Now I want to fill test_id by creating new rows in test. I nead a new entity each time so that I will have (1, 1), (2, 2), etc. I try to prepare update query with an insert statement but I don't understand how to do it. This is what I try:
update t2 set t2.test_id = t.id
from test2 t2 full join (INSERT INTO test(id) VALUES (default) RETURNING id) t on t2.test_id = t.id
but I get the following:
ERROR: syntax error at or near "INTO"
LINE 2: from test2 t2 full join (INSERT INTO test(id) VALUES (defaul...
^
SQL state: 42601
Character: 65
Can I create the query I want somehow?
Having just one column in the target table makes things a little tricky. It might be simpler to generate and assign the new ids first, using next_val, and then insert the values in test (we need option overriding system value to insert into a generated always colum,)
with t2 as (
update test2
set test_id = nextval('test_id_seq')
where test_id is null
returning test_id
)
insert into test(id) overriding system value
select test_id from t2
Demo on DB Fiddlde
Related
Dummy data to illustrate my problem:
create table table1 (category_id int,unit varchar,is_valid bool);
insert into table1 (category_id, unit, is_valid)
VALUES (1, 'a', true), (2, 'z', true);
create table table2 (category_id int,unit varchar);
insert into table2 (category_id, unit)
values(1, 'a'),(1, 'b'),(1, 'c'),(2, 'd'),(2, 'e');
So the data looks like:
Table 1:
category_id
unit
is_valid
1
a
true
2
z
true
Table 2:
category_id
unit
1
a
1
b
1
c
2
d
2
e
I want to update the is_valid column in Table 1, if the category_id/unit combination from Table 1 doesn't match any of the rows in Table 2. For example, the first row in Table 1 is valid, since (1, a) is in Table 2. However, the second row in Table 1 is not valid, since (2, z) is not in Table 2.
How can I update the column using postgresql? I tried a few different where clauses of the form
UPDATE table1 SET is_valid = false WHERE...
but I cannot get a WHERE clause that works how I want.
You can just set the value of is_valid the the result of a ` where exists (select ...). See Demo.
update table1 t1
set is_valid = exists (select null
from table2 t2
where (t2.category_id, t2.unit) = (t1.category_id, t1.unit)
);
NOTES:
Advantage: Query correctly sets the is_valid column regardless of the current value and is a vary simple query.
Disadvantage: Query sets the value of is_valid for every row in the table; even thoes already correctly set.
You need to decide whether the disadvantage out ways the advantage. If so then the same basic technique in a much more complicated query:
with to_valid (category_id, unit, is_valid) as
(select category_id
, unit
, exists (select null
from table2 t2
where (t2.category_id, t2.unit) = (t1.category_id, t1.unit)
)
from table1 t1
)
update table1 tu
set is_valid = to_valid.is_valid
from to_valid
where (tu.category_id, tu.unit) = (to_valid.category_id, to_valid.unit)
and tu.is_valid is distinct from to_valid.is_valid;
This question already has answers here:
sql server 2008 management studio not checking the syntax of my query
(2 answers)
Closed 4 years ago.
I have the following query which gives no error when I used a non-existent column reference in the subquery. The column which I referred in the subquery is actually a column in the table being updated.
create table tbl1 (f1 bigint, f2 char(10), f3 integer);
insert into tbl1 values (1, 'aa', 0);
insert into tbl1 values (2, 'bb', 0);
insert into tbl1 values (3, 'cc', 0);
insert into tbl1 values (4, 'dd', 0);
create table temp_tbl (ref_num bigint);
insert into temp_tbl values (1);
insert into temp_tbl values (3);
update tbl1 set f2='ok' where f1 in (select f1 from temp_tbl);
-- 4 records updated
can anyone tell me why it is not giving any error? and records are updated irrespective of the condition.
I tried this in both Oracle and SQLserver. results are same
The sub-query's column reference goes to the outer table!
update tbl1 set f2='ok' where f1 in (select f1 from temp_tbl);
Is read as
update tbl1 set f2='ok' where f1 in (select tbl1.f1 from temp_tbl);
Qualify your columns:
update tbl1 set f2='ok' where f1 in (select temp_tbl.ref_num from temp_tbl);
This is happening because the values in a SELECT don't just have to be columns from the table you're selecting from, the sub-query is returning the value for f1 from the outer query, instead of a value from temp_tbl.
Consider if you re-wrote the UPDATE query to:
SELECT *
FROM tbl1
WHERE f1 IN (select f1 from temp_tbl);
The results returned would actually be:
When you're trying to reason about something like this (and as a generally good way of working to get queries right!), it's useful to write your UPDATE query in the form:
UPDATE T
SET F2 = 'ok'
FROM TBL1 T
WHERE T.f1 IN
(
SELECT F1
FROM temp_tbl
)
By writing it this way you can readily comment out the UPDATE and SET components of the query, replace them with a SELECT and see what the set of data the query will operate on is.
Ok, trying to make this make sense and see if I can do this. I have multiple queries stored in SQL Server 2012 that I can run individually to get actual results. Each of these queries connect to a multitude of tables. What I want to do is take all of these queries and put them into a single query to get counts in one master list.
So for example. I have a query that looks for all records that have no email addresses. The next query looks for all records missing a phone number in a set field. The next query looks for records missing a filled field.
Each of these queries pull back results and I can run them one at a time. I want to set myself up a single query I can run to give me counts on each in a single results list.
I started doing a Union statement and put two of the query codes into it. The results came up like this:
NoEmail NoPhone
NULL 24486
74596 NULL
What I would like this to look like is this:
NoEmail NoPhone
74596 24486
Any ideas on how to do this?
I hope this is enough info and if not, let me know and I'll get you more.
Thanks.
You can do it like this:
Set up (for demonstration purposes only, so you can see the data I'm using):
create table t1 (
id numeric,
email varchar(20)
);
insert into t1 values (1,'test#example.com');
insert into t1 (id) values (2);
insert into t1 (id) values (3);
create table t2 (
id numeric,
phone varchar(20)
);
insert into t2 values (1,'123-456-7890');
insert into t2 (id) values (2);
insert into t2 (id) values (3);
insert into t2 (id) values (4);
insert into t2 (id) values (5);
Query:
select
(select count(id) from t1 where email is null) as NoEmail,
(select count(id) from t2 where phone is null) as NoPhone;
Result:
NoEmail NoPhone
2 4
You can add as many additional queries on to the end of the query as you'd like:
select
(select count(id) from t1 where email is null) as NoEmail,
(select count(id) from t2 where phone is null) as NoPhone,
(select ...) as anotherCol,
(select ...) as yetAnotherCol;
This question reflects my issue. How to do this in SQLite?
I've tried UPDATE with self-joins, isolating the self join in sub-query, triggers, and something similar to this. Here is an example:
UPDATE stage
SET title =
(
SELECT
prior.title
FROM
stage prior,
stage now
WHERE
prior.rownum+1 = now.rownum
)
WHERE
title is null
Every table in SQLite has got a pseudo-column called rowid (which can be accessible under several different names: rowid, oid, _rowid_, unless those names are assigned to other, real, columns). The rowid column is essentially a unique row identifier and you can use it as a sort criterion and/or in conditions.
The following query demonstrates how your problem can be solved with the help of rowid:
UPDATE stage
SET title = (
SELECT title
FROM stage AS prev
WHERE title IS NOT NULL AND prev.rowid < stage.rowid
ORDER BY prev.rowid DESC
LIMIT 1
)
WHERE title IS NULL
Here's a demo on SQL Fiddle.
You can read more about rowid in this SQLite manual.
I presented a solution for the problem you referred (I successfully tested on SQL2008, SQLite3 and Oracle11g). I copied that solution below:
CREATE TABLE test(mysequence INT, mynumber INT);
INSERT INTO test VALUES(1, 3);
INSERT INTO test VALUES(2, NULL);
INSERT INTO test VALUES(3, 5);
INSERT INTO test VALUES(4, NULL);
INSERT INTO test VALUES(5, NULL);
INSERT INTO test VALUES(6, 2);
SELECT t1.mysequence, t1.mynumber AS ORIGINAL
, (
SELECT t2.mynumber
FROM test t2
WHERE t2.mysequence = (
SELECT MAX(t3.mysequence)
FROM test t3
WHERE t3.mysequence <= t1.mysequence
AND mynumber IS NOT NULL
)
) AS CALCULATED
FROM test t1;
-- below here it was only tested in SQLite3, but I believe it should
-- work on other DBMS since it uses standard/non-proprietary SQL
UPDATE test
SET mynumber = (
SELECT t2.mynumber
FROM test t2
WHERE t2.mysequence = (
SELECT MAX(t3.mysequence)
FROM test t3
WHERE t3.mysequence <= test.mysequence
AND mynumber IS NOT NULL
)
);
I was wondering if it is possible to move all rows of data from one table to another, that match a certain query?
For example, I need to move all table rows from Table1 to Table2 where their username = 'X' and password = 'X', so that they will no longer appear in Table1.
I'm using SQL Server 2008 Management Studio.
Should be possible using two statements within one transaction, an insert and a delete:
BEGIN TRANSACTION;
INSERT INTO Table2 (<columns>)
SELECT <columns>
FROM Table1
WHERE <condition>;
DELETE FROM Table1
WHERE <condition>;
COMMIT;
This is the simplest form. If you have to worry about new matching records being inserted into table1 between the two statements, you can add an and exists <in table2>.
This is an ancient post, sorry, but I only came across it now and I wanted to give my solution to whoever might stumble upon this one day.
As some have mentioned, performing an INSERT and then a DELETE might lead to integrity issues, so perhaps a way to get around it, and to perform everything neatly in a single statement, is to take advantage of the [deleted] temporary table.
DELETE FROM [source]
OUTPUT [deleted].<column_list>
INTO [destination] (<column_list>)
All these answers run the same query for the INSERT and DELETE. As mentioned previously, this risks the DELETE picking up records inserted between statements and could be slow if the query is complex (although clever engines "should" make the second call fast).
The correct way (assuming the INSERT is into a fresh table) is to do the DELETE against table1 using the key field of table2.
The delete should be:
DELETE FROM tbl_OldTableName WHERE id in (SELECT id FROM tbl_NewTableName)
Excuse my syntax, I'm jumping between engines but you get the idea.
A cleaner representation of what some other answers have hinted at:
DELETE sourceTable
OUTPUT DELETED.*
INTO destTable (Comma, separated, list, of, columns)
WHERE <conditions (if any)>
Yes it is. First INSERT + SELECT and then DELETE orginals.
INSERT INTO Table2 (UserName,Password)
SELECT UserName,Password FROM Table1 WHERE UserName='X' AND Password='X'
then delete orginals
DELETE FROM Table1 WHERE UserName='X' AND Password='X'
you may want to preserve UserID or someother primary key, then you can use IDENTITY INSERT to preserve the key.
see more on SET IDENTITY_INSERT on MSDN
You should be able to with a subquery in the INSERT statement.
INSERT INTO table1(column1, column2) SELECT column1, column2 FROM table2 WHERE ...;
followed by deleting from table1.
Remember to run it as a single transaction so that if anything goes wrong you can roll the entire operation back.
Use this single sql statement which is safe no need of commit/rollback with multiple statements.
INSERT Table2 (
username,password
) SELECT username,password
FROM (
DELETE Table1
OUTPUT
DELETED.username,
DELETED.password
WHERE username = 'X' and password = 'X'
) AS RowsToMove ;
Works on SQL server make appropriate changes for MySql
Try this
INSERT INTO TABLE2 (Cols...) SELECT Cols... FROM TABLE1 WHERE Criteria
Then
DELETE FROM TABLE1 WHERE Criteria
You could try this:
SELECT * INTO tbl_NewTableName
FROM tbl_OldTableName
WHERE Condition1=#Condition1Value
Then run a simple delete:
DELETE FROM tbl_OldTableName
WHERE Condition1=#Condition1Value
You may use "Logical Partitioning" to switch data between tables:
By updating the Partition Column, data will be automatically moved to the other table:
here is the sample:
CREATE TABLE TBL_Part1
(id INT NOT NULL,
val VARCHAR(10) NULL,
PartitionColumn VARCHAR(10) CONSTRAINT CK_Part1 CHECK(PartitionColumn = 'TBL_Part1'),
CONSTRAINT TBL_Part1_PK PRIMARY KEY(PartitionColumn, id)
);
CREATE TABLE TBL_Part2
(id INT NOT NULL,
val VARCHAR(10) NULL,
PartitionColumn VARCHAR(10) CONSTRAINT CK_Part2 CHECK(PartitionColumn = 'TBL_Part2'),
CONSTRAINT TBL_Part2_PK PRIMARY KEY(PartitionColumn, id)
);
GO
CREATE VIEW TBL(id, val, PartitionColumn)
WITH SCHEMABINDING
AS
SELECT id, val, PartitionColumn FROM dbo.TBL_Part1
UNION ALL
SELECT id, val, PartitionColumn FROM dbo.TBL_Part2;
GO
--Insert sample to TBL ( will be inserted to Part1 )
INSERT INTO TBL
VALUES(1, 'rec1', 'TBL_Part1');
INSERT INTO TBL
VALUES(2, 'rec2', 'TBL_Part1');
GO
--Query sub table to verify
SELECT * FROM TBL_Part1
GO
--move the data to table TBL_Part2 by Logical Partition switching technique
UPDATE TBL
SET
PartitionColumn = 'TBL_Part2';
GO
--Query sub table to verify
SELECT * FROM TBL_Part2
Here is how do it with single statement
WITH deleted_rows AS (
DELETE FROM source_table WHERE id = 1
RETURNING *
)
INSERT INTO destination_table
SELECT * FROM deleted_rows;
EXAMPLE:
postgres=# select * from test1 ;
id | name
----+--------
1 | yogesh
2 | Raunak
3 | Varun
(3 rows)
postgres=# select * from test2;
id | name
----+------
(0 rows)
postgres=# WITH deleted_rows AS (
postgres(# DELETE FROM test1 WHERE id = 1
postgres(# RETURNING *
postgres(# )
postgres-# INSERT INTO test2
postgres-# SELECT * FROM deleted_rows;
INSERT 0 1
postgres=# select * from test2;
id | name
----+--------
1 | yogesh
(1 row)
postgres=# select * from test1;
id | name
----+--------
2 | Raunak
3 | Varun
If the two tables use the same ID or have a common UNIQUE key:
1) Insert the selected record in table 2
INSERT INTO table2 SELECT * FROM table1 WHERE (conditions)
2) delete the selected record from table1 if presents in table2
DELETE FROM table1 as A, table2 as B WHERE (A.conditions) AND (A.ID = B.ID)
It will create a table and copy all the data from old table to new table
SELECT * INTO event_log_temp FROM event_log
And you can clear the old table data.
DELETE FROM event_log
For some scenarios, it might be the easiest to script out Table1, rename the existing Table1 to Table2 and run the script to recreate Table1.