How to use a SQL for loop to insert rows into database?
I'm using Postgres, and I have a large number of rows that need to be inserted into the database, that differ only in terms of an开发者_JS百科 integer that is incremented. Forgive what may be a silly question, but I'm not much of a database guru. Is it possible to directly enter a SQL query that will use a loop to programatically insert the rows?
Example in pseudo-code of what I'm trying to do:
for i in 1..10000000 LOOP
INSERT INTO articles VALUES(i)
end loop;
Hopefully I've understood what you need (tested on 8.2):
INSERT INTO articles (id, name)
SELECT x.id, 'article #' || x.id
FROM generate_series(1,10000000) AS x(id);
In SQL Server you can do:
DECLARE @i int
SET @i = 1
WHILE @i<1000000
BEGIN
INSERT INTO articles
VALUES @i
SET @i=@i+1
END
Afaik, you can't write a loop directly as SQL, you'd have to create a stored procedure to do it.
This will do though (but someone can probably make it cleaner)
INSERT INTO articles WITH RECURSIVE i AS
(
SELECT 1 x
UNION ALL
SELECT x + 1
FROM i
WHERE x < 10000000
)
SELECT x
FROM i;
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