oracle中函数与存储过程

1. oracle函数

create function 函数名称 return 返回值类型 as
begin
... 
end 函数名称;

查询t_book表的count数
SQL> create function getBookCount return number as
begin
  declare book_count number;
  begin
    select count(*) into book_count from t_book;
    return book_count;
  end;
end getBookCount;
SQL> set serveroutput on;
begin
  dbms_output.put_line('表t_book有'|| getBookCount() ||'条数据');
end;
运行结果：
表t_book有4条数据

查询任意表的count数
SQL> create function getTableCount(table_name varchar2) return number as
begin
  declare recore_count number;
  query_sql varchar2(300);
  begin
    query_sql:='select count(*) from ' || table_name;
    execute immediate query_sql into recore_count;
    return recore_count;
  end;
end getTableCount;
SQL> begin
  dbms_output.put_line('表有'|| getTableCount('t_bookType') ||'条数据');
end;
运行结果：
表有2条数据

2. oracle存储过程

create procedure 存储过程名称 as
begin
... 
end 存储过程名称；

in只进不出
out只出不进
in out可进可出

增加book
SQL> create procedure addBook(bookName in varchar2,typeId in number) as
begin
  declare maxId number;
  begin
    select max(id) into maxId from t_book;
    insert into t_book values(maxId+1,bookName,typeId);
    commit;
  end;
end addBook;
SQL> execute addBook('java好东西',1);

增加book前判断重复
SQL> create procedure addBook2(bN in varchar2,typeId in number) as
begin
  declare maxId number;
  n number;
  begin
    select count(*) into n from t_book where bookName=bN;
    if(n>0) then
     return;
    end if;
    select max(id) into maxId from t_book;
    insert into t_book values(maxId+1,bN,typeId);
    commit;
  end;
end addBook2;
SQL> execute addBook2('java好东西',1);
SQL> execute addBook2('java好东西33',1);

out只出不进示例
SQL> create procedure addBook3(bN in varchar2,typeId in number,n1 out number,n2 out number) as
begin
  declare maxId number;
  n number;
  begin
    select count(*) into n1 from t_book;
    select count(*) into n from t_book where bookName=bN;
    if(n>0) then
     return;
    end if;
    select max(id) into maxId from t_book;
    insert into t_book values(maxId+1,bN,typeId);
    select count(*) into n2 from t_book;
    commit;
  end;
end addBook3;
SQL> declare n1 number;
        n2 number;
begin
  addBook3('onlyInNotOut',2,n1,n2);
  dbms_output.put_line('n1='||n1);
  dbms_output.put_line('n2='||n2);
end;
运行结果：
n1=7
n2=8

3. oracle存储过程debug

debug调试
Procedure --> addBook2 --> 右键Add debug infomation --> 右键Test