Oracle SQL 语句in长度不得超过1000
PL/SQL中,表达式/SQL本身的长度是可以达到比较长的长度(50K)左右,如:v_str:=:new.f1||:ndw.f2。。。 ; select :new.f1||:new.
1. IN 子句中的LIST个数最长为1000,超过该数目将报错,这里可转用一个临时表来解决;
2. * CREATE TRIGGER语句文本的字符长度不能超过32KB(触发器中不能使用LONG, LONG RAW 类型;触发器内可以参照LOB 类型列的列值,但不能通过 :NEW 修改LOB列中的数据;)顺便说一下,触发器中的PARENT关键字,只在嵌套表触发器中有效,
3. * 11G以前,DBMS_SQL对输入的SQL长度不能超过32K,原因是输入参数只能是VARCHAR2类型,11G后,可以用CLOB作为输入参数,则取消了这个限制
3. * 一个PL/SQL的包、过程、函数、触发器的大小,,在UNIX上最大是64K,而WINDOWS则是32K大小(32K这个应该不准,看下面的测试)
4. * SQL语句可以有多长?(网友说)Oracle文档说是64K,实际受一些工具的限制会较这个值低,但网友测试发现可以很长,甚至超过1M(我测试过 170K的都没问题)。具体多长,10G也未说明,只是与很多环境有关:数据库配置,磁盘空间,内存多少。。。
5. PL/SQL中,表达式/SQL本身的长度是可以达到比较长的长度(50K)左右,如:v_str:=:new.f1||:ndw.f2。。。 ; select :new.f1||:new.f2。。。 into v_str from dual; 另外发现,如果这样写:v_str := ‘a’||’b’||。。。则允许的表达式长度将大大的减少。如果表达式/SQL过长,超过了一个ORACLE包/过程允许的最大程序长度,则在编译时报 pls-123:program too large错误,这是pl/sql编译器本身的限制造成的,即表达式/SQL的长度在PL/SQL中受限于包/过程的最大大小

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