Oracle Databaseuses two engines to run PL/SQL blocks and subprograms.The PL/SQL engineruns procedural statements, whilethe SQL engineruns SQL statements. During execution,every SQL statement causes a context switch between the two engines, resulting in performance overhead. -- Oracle使用2个引擎来...
sql_notfound := SQL%NOTFOUND; -- assign value to Boolean variable check_status(part_id); IF sql_notfound THEN ... END; 如果SELECT INTO没有返回结果,PL/SQL就会抛出预定义异常NO_DATA_FOUND。如下例: BEGIN ... SELECT sal INTO my_sal FROM emp WHERE empno = my_empno; -- might raise...
Oracle Database uses two engines to run PL/SQL blocks and subprograms. The PL/SQL engine runs procedural statements, while the SQL engine runs SQL statements. During execution, every SQL statement causes a context switch between the two engines, resulting in performance overhead. -- Oracle 使用...
Rating: 3 PL/SQL 过程已成功完成。 例4:不同单元的引用 代码语言:javascript 代码运行次数:0 运行 AI代码解释 SQL> DECLARE 2 PROCEDURE p 3 IS 4 x VARCHAR2(1); 5 BEGIN 6 x := 'a'; -- Assign the value 'a' to x 7 DBMS_OUTPUT.PUT_LINE('In procedure p, x = ' || x); 8...
テスト PL/SQLの知識 その他の記事PL/SQLの基礎、パート1～11 詳細情報 BULK COLLECTとFORALL SQLインジェクション (PDF) ただし、OPEN-FORを動的SELECT文とともに使用することも可能です。次に、非常にシンプルな例を示します。 Copied to Clipboard ...
Log into the Distributor with the accounts used by the SQL Server service and the SQL Server Agent service and set the appropriate environment variables. The %ORACLE_HOME% variable should be set to refer to the installation point you specified when you installed the client networking software. Th...
When you select or fetch a physical rowid into aUROWIDvariable, you can use the functionROWIDTOCHAR, which converts the binary value to an 18-byte character string. Then, you can compare theUROWIDvariable to theROWIDpseudocolumn in theWHEREclause of anUPDATEorDELETEstatement to identify the la...
Try to locate SQL*PLUS on the Distributor. For an Oracle 10g client install, the name of this executable is sqlplus.exe. It is typically installed in %ORACLE_HOME%/bin. To verify that the path of SQL*PLUS appears in the system path, examine the value of the system...
For queries that return more than one row, you can explicitly declare a cursor to process the rows individually.A cursor is a handle to a specific private SQL area. In other words, a cursor can be thought of as a name for a specific private SQL area. A PL/SQL cursor variable enables...
The VARCHAR2 datatype stores variable-length character strings. Although you must assign a length to a VARCHAR2 datatype, this length is the maximum length for a value rather than the required length. Values assigned to a VARCHAR2 datatype aren’t padded with blanks. Because of this, a VAR...