游标遍历

-- 将user_tables的所有table_name以逗号间隔作为一个字符串输出 -- 通过for循环 显示游标 遍历 declare var_sql varchar2(32767) := ''; cursor cur is select table_name from user_tables order by table_name; begin for rec in cur loop var_sql := var_sql || rec.table_name || ','; end loop; var_sql := substr(var_sql, 1, length(var_sql) - 1); dbms_output.put_line(var_sql); end; -- 通过for循环 隐式游标 遍历 declare var_sql varchar2(32767) := ''; begin for rec in (select table_name from user_tables order by table_name) loop var_sql := var_sql || rec.table_name || ','; end loop; var_sql := substr(var_sql, 1, length(var_sql) - 1); dbms_output.put_line(var_sql); end; -- 通过loop..if遍历 declare cursor cur is select table_name from user_tables order by table_name; var_sql varchar2(32767) := ''; var_table_name user_tables.table_name%type; begin open cur; loop fetch cur into var_table_name; if cur%notfound then var_sql := substr(var_sql, 1, length(var_sql) - 1); exit; else var_sql := var_sql || var_table_name || ','; end if; end loop; close cur; dbms_output.put_line(var_sql); end; -- 通过loop..exit when遍历 declare cursor cur is select table_name from user_tables order by table_name; var_sql varchar2(32767) := ''; var_table_name user_tables.table_name%type; begin open cur; loop fetch cur into rec; exit when cur%notfound; var_sql := var_sql || var_table_name || ','; end loop; close cur; var_sql := substr(var_sql, 1, length(var_sql) - 1); dbms_output.put_line(var_sql); end; -- 通过loop..record类型遍历 declare cursor cur is select table_name from user_tables order by table_name; type type_rec is record( table_name user_tables.table_name%type); rec type_rec; var_sql varchar2(32767) := ''; begin open cur; loop fetch cur into rec; exit when cur%notfound; var_sql := var_sql || rec.table_name || ','; end loop; close cur; var_sql := substr(var_sql, 1, length(var_sql) - 1); dbms_output.put_line(var_sql); end;