I know the sequence can not be used in these places.
For a SELECT statement:
In a WHERE clause
In a GROUP BY or ORDER BY clause
In a DISTINCT clause
Along with a UNION or INTERSECT or MINUS
In a sub-query
Please help to achieve the below requirement with conditional insert.
Objective is - Need to insert if the name is not exist in the table as its protected by Sequence as primary key.
INSERT
WHEN EXISTS (SELECT 0 FROM TABLE1 WHERE NAME = 'DUPLICATE_NAME_TEST')
THEN
INTO TABLE1 (KEY, NAME, GROUP)
SELECT TESTSEQ.NEXTVAL, 'DUPLICATE_NAME_TEST', 30 FROM DUAL;
SQL has no INSERT WHEN construct. It does have WHERE. So you intend something like this:
INSERT INTO TABLE1 (NAME, GROUP)
SELECT 'DUPLICATE_NAME_TEST', 30
FROM DUAL
WHERE NOT EXISTS (SELECT 1 FROM TABLE1 T1 WHERE T1.NAME = 'DUPLICATE_NAME_TEST');
Related
I am facing a hive problem.
I will get a 0 or 1 after from sql
"select count(*) from table1 where ..."
If the result is 1, then I will execute the sql
"Insert Into table2 partition(d) (select xxxx from table 1 where ...
group by t)"
Otherwise do nothing.
My question is how can I write these two sql together into one sql. I am only allowed to write a single long sql.
I tried to put the first sql into the where condition in sql2, but it throwed an error said it's not supported to operat on table1 in the subquery (couldn't remember clearly, something like this).
It sounds like a very easy question for experienced programmers, but I just started lerning hive for 2 days.
If select in insert overwrite table partition does not returns rows, nothing is being overwritten.
So, just calculate your count in the same dataset and filter by it, use analytics funtion if you want to aggregate data on different level before insert
Insert Into table2 partition(d)
select col1, col2, sum(col3), etc, etc, partition_col
from
(
select --some columns here,
--Assign the same count to all rows
count(case when your_boolean_condition then 1 else null end) over () as cnt
from table 1
) s
where cnt=1 --If this is not satisfied, no overwrite will happen
AND more_conditions
group by ...
Another approach possible is to use cross-join with your count:
insert Into table2 partition(d)
select xxxx ... ... ..., partition_column as d
from
(
select t.*, c.cnt
table1 t cross join (select count(*) cnt from table1 where condition) c
)s
where cnt=1 <and another_condition>
I've got a query like this
select column, count(*)
from mytable
where column in ('XXX','YYY','ZZZ',....)
group by column;
But I want also to get a row for values the aren't in the table.
Let's suppose that 'ZZZ' doesn't exist in mytable, I'd like to get:
COLUMN COUNT(*)
XXX 3
YYY 2
ZZZ 0 (or NULL)
Oracle version 10g
Thanks in advance
Mark
In general, you would need to have a second table which contains all the possible column values whose counts you want to appear in the output. For demo purposes only, we can use a CTE for that:
WITH vals AS (
SELECT 'XXX' AS val UNION ALL
SELECT 'YYY' UNION ALL
SELECT 'ZZZ'
)
SELECT t1.val, COUNT(t2.col) AS cnt
FROM vals t1
LEFT JOIN mytable t2
ON t2.col = t1.val
GROUP BY
t1.val;
Using SQL Server, I have two tables that I want to merge. Table2 has a tbID column that has NULL values. I would like for NULL values to be automatically updated, beginning with the next value of the tbID column, from Table1 when the tables are merged.
I am entering something like this..
SELECT
A.tbID,
A.etID,
A.cNumber,
A.cName
FROM
Table1 AS A
UNION ALL
SELECT
B.tbID,
B.etID,
B.cNumber,
B.cName
FROM
Table2 AS B
My results has a NULL value (instead of an automatically inserted number), in the records from Table2.
If by "merge" you want all the records to end up in table1 - just leave the id column out of the insert:
INSERT INTO table1 (etID, cNumber, cName)
SELECT etID, cNumber, cName
FROM table2
If you just want to select and see incremented ids for the data coming from table2, here is one way:
SELECT A.tbID,
A.etID,
A.cNumber,
A.cName
FROM Table1 AS A
UNION ALL
SELECT (SELECT MAX(tbID) FROM Table1) +
ROW_NUMBER() OVER (ORDER BY B.etID),
B.etID,
B.cNumber,
B.cName
FROM Table2 AS B
If you just want a result set, you can use:
SELECT A.tbID, A.etID, A.cNumber, A.cName
FROM Table1 A
UNION ALL
SELECT (a.maxID + ROW_NUMBER() OVER (ORDER BY (SELECT NULL))) as tbID,
B.etID, B.cNumber, B.cName
FROM Table2 B CROSS JOIN
(SELECT MAX(A.tbID) as maxID FROM Table1 as A) a;
If you are inserting these rows into a new table, then the id can be assigned automatically -- but the values might differ for A.
Does Big Query support operations like "REPLACE INSERT" or something related to that?
If I run a query like this twice:
INSERT INTO table(column1) VALUES(1)
It'll create a duplicated row, is it possible to insert a row only if a column with the same value does not exist?
Thanks!
Below should make it
#standardSQL
INSERT INTO yourTable(column1)
SELECT value FROM (SELECT 1 AS value)
LEFT JOIN yourTable
ON column1 = value
WHERE column1 IS NULL
Does this work for you?
INSERT INTO table(column1)
WITH s AS (SELECT 1 src)
SELECT src FROM s WHERE NOT EXISTS (
SELECT * FROM table t WHERE t.column1 = s.src
)
I'd like to insert random names of table 2 into the records of table 1.
Table 1: ID ... Name ... FurtherData
Table 2: Name
Is it possible to achieve this in a simple SQL statement?
Kind regards
I think, you want to insert all names from table2 into table1 those are not already there
INSERT INTO Table1 (name)
SELECT table2.Name
From table2
Where table2.Name NOT IN (SELECT table1.Name From table1)
Something like this to get 100 random names:
insert into table1(name)
select name
from (select name
from table2
order by dbms_random.random()
) t
where rownum <= 100;
Of course, you may want to supply values for the other columns, but your question seems to be specifically about getting random values from the second table.
In Oracle 12, you don't need the subquery. You can use fetch first <n> rows only.