如何在plsql中初始化一个矩阵 [英] How to initialize a matrix in plsql

问题描述

我试图用关联数组映射一个表，但我无法弄清楚如何初始化它。

以下是一个例子：

 类型记录类型记录
（
 value1 NUMBER，
 value2 NUMBER，
 value3 NUMBER 
）; 
 TYPE TblType IS RecType的表格INDEX BY PLS_INTEGER; 
 TYPE TblOfTblType是TblType INDEX BY PLS_INTEGER的表格; 
矩阵TblOfTblType; 
  

现在，当我试图初始化这个矩阵时：

  FOR IN IN matrix.FIRST .. matrix.LAST LOOP 
 FOR j IN矩阵（i）.FIRST ..矩阵（i）.LAST LOOP 
矩阵（i）（j）：= NULL; 
 END LOOP; 
 END LOOP; 
  

这行不通！我也试过

  matrix：= TblOfTblType（）（）; 
  

显示以下错误：

PLS-00363表达式'Matrix'不能用作赋值目标。

解决方案你不需要使用关联数组 - 一个集合就可以工作。

  DECLARE 
 TYPE RecType IS RECORD 
（
 value1 NUMBER，
 value2 NUMBER，
 value3 NUMBER 
）; 
 TYPE TblType是RecType的表格; 
 TYPE TblOfTblType是TblType的表格; 
矩阵TblOfTblType：= TblOfTblType（）; 
 BEGIN 
 matrix.EXTEND（3）; 
 FOR I IN 1 .. matrix.COUNT LOOP 
 matrix（i）：= TblType（）; 
矩阵（i）.EXTEND（4）; 
 FOR j IN 1 ..矩阵（i）.COUNT LOOP 
矩阵（i）（j）.value1：= i; 
矩阵（i）（j）.value2：= j; 
矩阵（i）（j）.value3：= DBMS_RANDOM.VALUE; 
 END LOOP; 
 END LOOP; 
 
 FOR i 1 .. matrix.COUNT LOOP 
 FOR j IN 1 .. matrix（i）.COUNT LOOP 
 DBMS_OUTPUT.PUT（'['|| matrix（ i）（j）.value1 
 ||'，'|| matrix（i）（j）.value2 
 ||'，'|| matrix（i）（j）.value3 ||' ]'|| CHR（11））; 
 END LOOP; 
 DBMS_OUTPUT.NEW_LINE; 
 END LOOP; 
 END; 
 / 
  

I've tried to Map a table with associative arrays , but i can't figure out how to initialize it

here is an example :

TYPE RecType IS RECORD
 (
  value1   NUMBER,
  value2   NUMBER,
  value3   NUMBER
 );
 TYPE TblType IS TABLE OF RecType INDEX BY PLS_INTEGER;
 TYPE TblOfTblType IS TABLE OF TblType INDEX BY PLS_INTEGER;
 matrix   TblOfTblType;

Now when i tried to initialize the matrix like this :

FOR i IN matrix.FIRST .. matrix.LAST LOOP
  FOR j IN matrix (i).FIRST .. matrix (i).LAST LOOP
       matrix(i)(j) := NULL;  
  END LOOP;
END LOOP;

It doesn't work !I also tried

matrix := TblOfTblType()();

it shows the following error :

PLS-00363 expression 'Matrix' cannot be used as an assignment target .

解决方案

You do not need to use an associative array - a collection will work.

DECLARE
  TYPE RecType IS RECORD
  (
    value1   NUMBER,
    value2   NUMBER,
    value3   NUMBER
  );
  TYPE TblType IS TABLE OF RecType;
  TYPE TblOfTblType IS TABLE OF TblType;
  matrix   TblOfTblType := TblOfTblType();
BEGIN
  matrix.EXTEND(3);
  FOR i IN 1 .. matrix.COUNT LOOP
    matrix(i) := TblType();
    matrix(i).EXTEND(4);
    FOR j IN 1 .. matrix(i).COUNT LOOP
      matrix(i)(j).value1 := i;
      matrix(i)(j).value2 := j;
      matrix(i)(j).value3 := DBMS_RANDOM.VALUE;
    END LOOP;
  END LOOP;

  FOR i IN 1 .. matrix.COUNT LOOP
    FOR j IN 1 .. matrix(i).COUNT LOOP
      DBMS_OUTPUT.PUT( '[' || matrix(i)(j).value1
                    || ',' || matrix(i)(j).value2
                    || ',' || matrix(i)(j).value3 || ']' || CHR(11) );
    END LOOP;
    DBMS_OUTPUT.NEW_LINE;
  END LOOP;
END;
/

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