oracle数据库高级应用之《自动生成指定表的insert，update，delete语句》

 /*
 * 多条记录连接成一条
 * tableName 表名
 * type 类型：可以是insert/update/select之一
 */
 create or replace function my_concat(tableName varchar2,type varchar2)
 return varchar2
 is
  type typ_cursor is ref cursor;
  v_cursor typ_cursor;
  v_temp varchar2(30);
  v_result varchar2(4000):= '';
  v_sql varchar2(200);
 begin
  v_sql := 'select COLUMN_NAME from user_tab_columns where table_name = ''' || upper(tableName) || ''' order by COLUMN_ID asc';
  open v_cursor for v_sql;
  loop
     fetch v_cursor into v_temp;
     exit when v_cursor%notfound;
     if type = 'select' or type = 'insert' then
        v_result := v_result ||',' || v_temp;
     elsif type = 'update' then
        v_result := v_result ||',' || v_temp || ' = ?';
     elsif type = 'javabean' then
        v_result := v_result ||',bean.get' || upper(substr(v_temp,1,1)) || lower(substr(v_temp,2)) ||  '()';
     end if;
  end loop;
  return substr(v_result,2);
 end;  

 /*
 * 通过表名自动生成insert/update/select/javabean get方法语句
 * tableName 表名
 * type 类型：可以是insert/update/select之一
 */
 create or replace procedure autoGenerateSQL(
 tableName varchar2,
 type varchar2,
 out_result out varchar2
 )
 is
   sql_insert varchar2(2000);
   sql_update varchar2(2000);
   sql_select varchar2(2000);
   javabean_str varchar2(2000);
   field_num integer;        --字段个数
   type_info varchar2(20);   --参数类型判断信息
 begin  

 sql_insert := 'insert into ' || upper(tableName) || '(' || my_concat(tableName,type) || ') values (';
 sql_update := 'update ' || upper(tableName) || ' set ';
 sql_select := 'select ';
 javabean_str := '';
 type_info := '';  

 select count(*) into field_num from user_tab_columns where table_name=upper(tableName);
 select decode(type,'insert',type,'update',type,'select',type,'javabean',type,'error') into type_info from dual;  

 if field_num = 0 then             -- 表不存在时
    out_result := '表不存在！请重新输入!';
 elsif type_info = 'error' then    --type参数错误时
    out_result := 'type参数错误：类型只能是insert、update、select、javabean之一';
 elsif field_num > 0 then
   if type = 'insert' then         --生成insert 语句
     for i in 1..field_num
       loop
          sql_insert := sql_insert || '?';
          if i < field_num then
             sql_insert := sql_insert || ',';
          end if;
       end loop;
       sql_insert := sql_insert || ')';
       out_result := sql_insert;
   elsif type = 'update' then      --生成update 语句
       sql_update := sql_update || my_concat(tableName,type);
       out_result := sql_update;
   elsif type = 'select' then      --生成select 语句
       sql_select := sql_select || my_concat(tableName,type) || ' from ' || upper(tableName) || ' a';
       out_result := sql_select;
   elsif type = 'javabean' then    --生成javabean的get方法
       javabean_str := my_concat(tableName,type);
       out_result := javabean_str;
   end if;
 end if;  

 end autoGenerateSQL; 

 declare out_result varchar2(512);
 begin
 autoGenerateSQL('tf_Employee2','insert', out_result);
 dbms_output.put_line(out_result);
 end;