I can't get this SQL statement right. I want to select band emails into another table but I don't understand what I'm doing wrong:
INSERT INTO submitted (mail)
SELECT
submitted.bandid,
band.mail,
band.id
FROM
band
WHERE
submitted.bandid = band.id
Can anybody help me?
Try this, you had specified 1 column to INSERT INTO but your SELECT query contained 3 columns, also the tables in your weren't joined:
INSERT INTO submitted (mail)
SELECT
band.mail
FROM band
INNER JOIN submitted ON submitted.bandid = band.id
You haven't mentioned the error message you're getting, but I suspect the problem is that you only have one column specified in the INSERT part of the statement, but the SELECT part returns many columns.
This w3schools page has a good example of how this query should be structured:
Copy only some columns from one table into another table:
INSERT INTO table2 (column1, column2, column3, ...)
SELECT column1, column2, column3, ...
FROM table1
WHERE condition;
I suspect you want update, not insert:
UPDATE s
SET mail = b.mail
FROM submitted s JOIN
band b
ON s.bandid = b.id;
insert inserts new rows into the table. update updates columns in existing rows.
Related
Let's say var_Environment = QA1,QA2.
I have two tables table 1 and table 2. Table 1 has some column name var_Environment =QA1; where as table 2 does have the same column name but no values
Now my task is, I need to copy all the values from table1 to table2 only if condition meets var_Environment =QA2 How will I perform this operation ? Can I use Union All with some condition? Can someone help?
You can use INSERT INTO SELECT like below.
The WHERE clause may need adjustment, so run the the SELECT query by itself to check if the correct rows are selected.
INSERT INTO table2
SELECT var_Environment
FROM Table1
WHERE var_Environment LIKE '%QA2%'
I have been trying to copy the data listed in one table to another that are both located in the same database. However, every time I have everything entered, it runs the query and says 0 rows updated.
I have tried several variations in an attempt to get this to work. One such attempt is as listed below. I found this while researching in an attempt to get this done.
UPDATE
t1
SET
t1.column = t2.column
FROM
Table1 t1
INNER JOIN Table2 t2
ON t1.id = t2.id;
Any help on this would be greatly appreciated.
UPDATE will only modify records that already exist, if you want to insert rows that exist on another table use INSERT.
You can combine INSERT and SELECT to copy a whole table1 into a table2.
INSERT INTO table2 SELECT * FROM table1;
You can use INSERT IGNORE to copy only records that don't exist yet (based on unique keys).
You can also specify fields to copy in case the tables are different:
INSERT INTO table2 (id, first_name, last_name) SELECT id, name, surname FROM table1;
I am trying to insert the distinct values in my database:
My query is like that:
query2 = "INSERT INTO users (id, name, screenName, createdAt, defaultProfile, defaultProfileImage,\
description) SELECT DISTINCT %s, %s, %s, %s, %s, %s, %s;"
cur.execute(query2, (user_id, user_name, user_screenname, user_createdat, \
default_profile, default_profile_image, description))
However, I still get the error: psycopg2.IntegrityError: duplicate key value violates unique constraint "users_key".
I guess that the query is inserting all data and then selects the distinct values?
Another way I guess would be to store all data in a temporary database and then retrieve them for there.
But is there an easier way?
Thank you!
You appear to be trying to do an insert ... if not exists type operation. If you're on PostgreSQL 9.5 you should use INSERT ... ON CONFLICT NO ACTION. See How to UPSERT (MERGE, INSERT ... ON DUPLICATE UPDATE) in PostgreSQL? for relevant details.
SELECT DISTINCT, used the way you are using it, will not help you with this. It operates only on the rows input to the SELECT statement. It doesn't know anything about where the output rows go, in your case to a table.
You need to join against the table, or use WHERE NOT EXISTS (SELECT 1 FROM mytable WHERE ...) to make the INSERT INTO ... SELECT ...'s SELECT part return zero rows if the row already exists in the target table.
Note, though, that that's still subject to race conditions. If you have multiple concurrent clients you also need to LOCK the table.
For anyone who is looking for a way to insert unique values from one table into a table where there is no unique key (in other words, only insert rows wherein the full set of columns does not match a set of columns for an existing record in the target table)
e.g.
Table 1
column1 column2
------- -------
1. dog collar
Table 2
column1 column2
------- -------
1. dog collar
2. dog leash
Intended effect is to insert column 2 from Table 2, but not column 1 since it matches a row in Table 1.
This worked for me, albeit not very performant:
INSERT INTO table1 (
column1,
column2
)
SELECT
column1,
column2
FROM table2
WHERE (
column1,
column2
)
NOT IN
(SELECT
column1,
column2
FROM table1)
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Oracle: how to UPSERT (update or insert into a table?)
Could you guys give me an suggestion on how to proceed in the below situation:
Read table 2 column 1
if value says the record exists in table 1
update table 1 record with table 2 record details
else(value says the record does not exist in table 1)
insert table 1 record with table 2 record details
I am beginner to Oracle SQL, Please let me know if there is a better approach..I was thinking about using cursors to solve this..
The simplest answer is to use the merge statement:
MERGE INTO table1 a
USING ( select column1, column2
from table2 ) b
ON ( a.column1 = b.column1 )
WHEN MATCHED THEN
update set a.column2 = b.column2
WHEN NOT MATCHED THEN
insert (a.column1, a.column2)
values (b.column1, b.column2)
Simply put this takes everything from the select on table2. It then joins this query to table1 on the condition. If there is a "match" then it updates, otherwise inserts.
The documentation has more information about various additional options that you don't, currently, require.
Have a look at the merge statement.
http://psoug.org/reference/merge.html
How could I, in SQL Server 2008, write a SQL statement that would insert one row for each distinct value it finds in one column in the same table?
Edit:
The table I want to add rows to the same table I'm checking.
I have normalized table with a column [Name], and [Hobby], so how do I insert one new hobby for each name?
Input greatly appreciated =]
try
INSERT INTO TargetTable (SomeColumn)
SELECT DISTINCT TheSourceColumn From SomeSourceTable;
IF that is not what you are looking for please provide more details like what the data model looks like etc.
UPDATE - after edit from OP:
I am not sure that you data model is good but you can do this:
INSERT INTO TheTable (NAME, HOBBY)
SELECT DISTINCT X.NAME, #SomeHOBBY FROM TheTable X;
You could use something like
Insert into table1
Select distinct col1 from tabl2
The above should work as long as table1 has just one column of the same data type as col1 of tabl2