数据库查询(50分)

S

sanji

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GUEST, unregistred user!

• 1999-06-08

• #1

我在查询上用了两个datetimepicker,然后与库中的日期字段的值做比较,
要求字段中的日期如果在datetimepicker1和datetimepicker2之间
则将记数器加一,直到table1.eof=true为止.
求源码,望大家赐教!

 

李

李颖

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GUEST, unregistred user!

• 1999-06-08

• #2

1、
with Table1 do
begin
Count:=0;
First;
while not eof do
begin
if (FieldByName('FieldA').AsDateTime>=DateTimePicker1.Date) and
(FieldByName('FieldA').AsDateTime<=DateTimePicker2.Date) then
Inc(Count);
Next;
end;
end;

2、
SQL.Text:='Select count(*) from MyTable'
+' where FieldA>=ate1'
+' and FieldB<=ate2'

 

K

KCZ

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GUEST, unregistred user!

• 1999-06-08

• #3

a test

 

J

JAYLV

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GUEST, unregistred user!

• 1999-06-08

• #4

如使用SQL SERVER

WITH TABLE1 DO
BEGIN
INDEXFIELDNAMES:='FIELDA';
SETRANGESTART;
FieldByName('FieldA').AsDateTime=DateTimePicker1.Date;
SETRANGEEND;
FieldByName('FieldA').AsDateTime=DateTimePicker2.Date;
APPLYRANGE;
COUNT:=RECORDCOUNT;
END;

如为PARADOX库,建一索引

 

W

wgzhang

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GUEST, unregistred user!

• 1999-06-08

• #5

别多说了,李颖的方法2最佳

 

S

sanji

Unregistered / Unconfirmed

GUEST, unregistred user!

• 1999-06-09

• #6

接受答案了.