SQL INDEX

create index log_id on log_records(id);

create index log_dt_id on log_records(datetime);

create index log_rrdt_id on relay_records(datetime);

create index log_crdt_id on card_records(datetime);

JAVA 取得可用字型名稱

String[] fontList = GraphicsEnvironment.getLocalGraphicsEnvironment()
.getAvailableFontFamilyNames();

SQL 隨機取一筆

SQL Server 2005

SELECT TOP 1 Field1, …, FieldN
FROM Table1
ORDER BY NEWID()

Access

SELECT TOP 1 Field1 , …, FieldN
FROM Table1
ORDER BY Rnd(Field1)

MySQL

SELECT Field1, …, FieldN
FROM Table1
ORDER BY RAND()
LIMIT 1

Oracle 10g Express

SELECT Field1, …, FieldN
FROM ( SELECT Field1, …, FieldN
FROM Table1
ORDER BY dbms_random.value)
WHERE rownum <= 1

SQLite 3

SELECT Field1, …, Field2
FROM Table1
ORDER BY Random()
LIMIT 1

PostgreSQL 8.3

SELECT “Field1″, “…”, “FieldN”
FROM “Table1″
ORDER BY RANDOM()
LIMIT 1

SQL IF ELSE

if not exists (select TOP(1) * from test_result_list where sub_cls_id ='C0000001-001' AND empno = '00000046')

insert into test_result_list (sub_cls_id,empno,is_pass,point) values('C0000001-001','00000046',0,12)

else

update test_result_list set sub_cls_id = 'C0000001-001',empno='00000046',is_pass=1,point=70 where sub_cls_id = 'C0000001-001' AND empno='00000046'