Getting the latest record
How can I get the Lastest record from SQL
DROP TABLE placement
I have a table like this:
balance keepplace startdate ___________________________________ A01 floor 1 2002-10-10 A01 BBB 2001-08-08 A02 222 2002-07-08 A02 111 2000-01-01 A03 ....
I want to get " where is the keep place for all balance by now? Answer Use a sub-select to get the last date - and make that match the original...
CREATE TABLE placement(balance CHAR(3)
,keepplace VARCHAR(10)
,startdate DATE
,PRIMARY KEY(balance,startdate)
);
INSERT INTO placement VALUES('A01','floor 1','10 Oct 2002');
INSERT INTO placement VALUES('A01','BBB','08 Aug 2002');
INSERT INTO placement VALUES('A02','222','08 Jun 2002');
INSERT INTO placement VALUES('A02','111','01 Jan 2002');
SELECT balance, keepplace, startdate
FROM scott.placement, (
SELECT balance AS B, MAX(startdate) AS S
FROM scott.placement
GROUP BY balance)
WHERE startdate = S
USE scott;
CREATE TABLE placement(balance CHAR(3)
,keepplace VARCHAR(10)
,startdate DATETIME
,PRIMARY KEY(balance,startdate)
);
INSERT INTO placement VALUES('A01','floor 1','10 Oct 2002');
INSERT INTO placement VALUES('A01','BBB','08 Aug 2002');
INSERT INTO placement VALUES('A02','222','08 Jun 2002');
INSERT INTO placement VALUES('A02','111','01 Jan 2002');
SELECT balance, keepplace, startdate
FROM placement, (
SELECT balance AS B, MAX(startdate) AS S
FROM placement
GROUP BY balance) X
WHERE startdate = X.S
CREATE TABLE placement(balance CHAR(3) NOT NULL
,keepplace VARCHAR(10)
,startdate DATE NOT NULL
,PRIMARY KEY(balance,startdate)
);
INSERT INTO placement VALUES('A01','floor 1','2002-10-10');
INSERT INTO placement VALUES('A01','BBB','2002-08-08');
INSERT INTO placement VALUES('A02','222','2002-07-08');
INSERT INTO placement VALUES('A02','111','2002-01-01');
DROP TABLE X;
CREATE TABLE X (
B CHAR(3) NOT NULL PRIMARY KEY
,S DATE
);
INSERT INTO X
SELECT balance AS B, MAX(startdate) AS S
FROM placement
GROUP BY balance;
SELECT balance, keepplace, startdate
FROM placement, X
WHERE startdate = X.S
CREATE TABLE placement(balance CHAR(3)
,keepplace VARCHAR(10)
,startdate DATE
,PRIMARY KEY(balance,startdate)
);
INSERT INTO placement VALUES('A01','floor 1','10 Oct 2002');
INSERT INTO placement VALUES('A01','BBB','08 Aug 2002');
INSERT INTO placement VALUES('A02','222','08 Jun 2002');
INSERT INTO placement VALUES('A02','111','01 Jan 2002');
SELECT balance, keepplace, startdate
FROM placement, (
SELECT balance AS B, MAX(startdate) AS S
FROM placement
GROUP BY balance) X
WHERE startdate = X.S
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