Declare是一个语言元素。 删除Delete运算符将从对象中删除满足“属性”窗格中的可选谓词的行。 Deleted Scan在触发器中,Deleted Scan运算符扫描已删除的表。 无DistinctDistinct运算符可以从行集或值集中删除重复项。 Distinct是一个逻辑运算符。 无Distinct SortDistinct Sort逻辑运算符将对输入进行扫描,删除重复项...
Define, allocate, and release acursor(DECLARE CURSOR,OPEN,CLOSE). Specify a database and connect to it (DECLARE DATABASE,CONNECT). Assign variable names (DECLARE STATEMENT). Initialize descriptors (DESCRIBE). Specify how error and warning conditions are handled (WHENEVER). ...
DECLARE @MyNumber1 int, @MyNumber2 int, @MyResult1 int, @MyResult2 int SELECT @MyNumber1 = 144, @MyNumber2 = 121 -- Assign the function result to the variable: SELECT @MyResult1 = SQRT(@MyNumber1), @MyResult2 = SQRT(@MyNumber2) -- Return the variable value SELECT @MyResult1...
You declare PL/SQL variables, constants and types in declare block. The syntax is <name> [CONSTANT] <datatype> [NOT NULL] [:= | DEFAULT <expr>] <name> is the name of the variable or constant; <datatype> may be scalar, composite datatype, reference or LOB; <expr> is a literal v...
In SQL Server 2012, you can set a variable’s initial value at the same time you declare it. For example, the following line of code declares a variable named @ctr of type int and sets its value to 100:DECLARE @ctr int = 100
Define, allocate, and release cursors (DECLARE CURSOR, OPEN, CLOSE) Specify a database and connect to Oracle (DECLARE DATABASE, CONNECT) Assign variable names (DECLARE STATEMENT) Initialize descriptors (DESCRIBE) Specify how error and warning conditions are handled (WHENEVER) Parse and run SQL ...
游标定义及操纵语句(DECLARE CURSOR、OPEN、FETCH、CLOSE) 事务控制语句(COMMIT、ROLLBACK) 动态SQL 执行语句(EXECUTE IMMEDIATE) 注意 SQL语句必须以分号结尾,否则语法分析报错。 异常处理部分用于处理存储过程在执行过程中可能出现的错误。 下面是一个定义存储过程的简单示例: ...
Declare and initialize variables in the declaration section. Assign new values to variables in the executable section. Pass values into PL/SQL blocks through parameters. View results through output variables. 变量的类型: PL/SQL variables Non-PL/SQL variables: Bind and host variables(用在sqlplus和i...
CONTEXT: PL/SQL function inline_code_block line 3 during statement block local variable initialization 1. 2. 3. 4. 5. 示例12-15 声明中触发的异常由上层块处理 \set SQLTERM / BEGIN DECLARE credit_limit CONSTANT NUMBER(3) := 5000; BEGIN NULL; END; EXCEPTION WHEN VALUE_ERROR THEN RAISE ...
-- Passing the function value as a variable.DECLARE@CheckDate datetime;SET@CheckDate =GETDATE(); EXEC dbo.uspGetWhereUsedProductID 819, @CheckDate; GO 指定参数名称 创建过程并声明参数名时,参数名必须以一个@字符开头,并且必须在过程范围内是唯一的。