Firebird 2.1发行注记

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没有truncate table还是不方便，递归还是挺快的

SQL> truncate table t;
Statement failed, SQLSTATE = 42000
Dynamic SQL Error
-SQL error code = -104
-Token unknown - line 1, column 1
-truncate
SQL> delete from t;
Current memory = 10991328
Delta memory = -11304
Max memory = 75050136
Elapsed time= 6.92 sec
Buffers = 2048
Reads = 15650
Writes 15551
Fetches = 5031281
SQL> insert into t
CON> with RECURSIVE r as(select 1 a from rdb$database union all select a+1 a from r where a<1000)
CON> ,t2 as(select t0.a*999+t1.a as L from r as t0,r as t1)
CON> select mod(L,4)c1,mod(L,5)c2,mod(L,67)c3,
CON> mod(case when mod(L,13)>0 then L end ,113)c4, L v from t2;
Current memory = 11027152
Delta memory = 35824
Max memory = 75050136
Elapsed time= 11.85 sec
Buffers = 2048
Reads = 22
Writes 15699
Fetches = 3132166

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删除记录不能减小fdb文件大小

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SQL> select rand() from rdb$database;

                   RAND
=======================
     0.7863636932492185

SQL> select rand() from rdb$fields rows 10;

                   RAND
=======================
     0.7481975987886105
     0.1316007974459129
     0.5644066697191158
     0.6604946355086617
     0.7547819530286933
     0.1430457704918935
     0.8128152580636652
     0.5951363006707321
     0.9737852420749619
     0.6942684065021024

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翻出家里一本interbase数据库开发，2004年的，6年了还有用

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http://product.dangdang.com/product.aspx?product_id=9053078

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pdf http://u.115.com/file/f1dd970647