CREATE OR REPLACE FUNCTION example_function() RETURNS VOID AS $$ DECLARE local_variable INTEGER := 0; another_variable TEXT; BEGIN -- 为变量赋值 local_variable := local_variable + 1; -- 使用变量进行查询 SELECT 'The local variable is ' || local_variable INTO another_variable; -- 输出结果...
CREATE OR REPLACE FUNCTION func_declarell() RETURNS text AS $$ DECLARE --Variable store declared not null with a default value. nanvar VARCHAR NOT NULL := 'notnull text';--Declaring an integer to hold integer constant. digit CONSTANT INTEGER := 10; /* declaring variable with a default va...
带有两个select语句的PostgreSQLFunction 、、、 我试图创建一个PostgreSQL函数,声明两个变量来返回每个变量--不同查询的结果,查询本身非常简单,并且依赖于具有不同条件的相同选择:和表的结构也很简单,有三行: 版本 浏览2提问于2018-11-21得票数1 回答已采纳 ...
DO $$ DECLARE variable_name data_type; BEGIN variable_name := value; -- 在此处编写使用变量的代码 END $$; 复制代码 在函数或存储过程中,可以声明变量并在函数或存储过程中使用该变量。 CREATE OR REPLACE FUNCTION function_name() RETURNS void AS $$ DECLARE variable_name data_type; BEGIN variable_...
DO $$ DECLARE my_variable INTEGER := 42; my_string TEXT := 'Hello, World!'; BEGIN RAISE NOTICE 'my_variable: %, my_string: %', my_variable, my_string; END $$; 在此示例中,我们声明了两个变量 my_variable 和my_string,并分别赋予了整数和字符串值。然后在 BEGIN 和END 之间使用 RAISE...
GREATE[OR REPLACE]FUNCTION function_name (arguments)RETURNSreturn_datatype AS $variable_name$DECLAREDeclaration; [...]BEGIN<function_body>[...] RETURN{variable_name|value}END;LANGUAGEplpgsql; 参数说明: [OR REPLACE]:是可选的,叫上表示允许修改和替换现有函数。
] ) CREATE TYPE name ( INPUT = input_function, OUTPUT = output_function [, RECEIVE = receive_function ] [, SEND = send_function ] [, ANALYZE = analyze_function ] [, INTERNALLENGTH = { internal_length | VARIABLE } ] [, PASSEDBYVALUE ] [, ALIGNMENT = alignment ] [, STORAGE = stor...
2. Function Logic: The RETURN QUERY uses the variable bonus_rate to calculate bonuses for employees with a salary above the threshold. Example 3: Default Values in Variables Code: DO$$DECLAREtax_rateNUMERICDEFAULT0.05;-- Declare with a default valuetotal_salaryNUMERIC;BEGIN-- Assign the sum of...
In PostgreSQL, a variable is always declared with a particular data type, such as INTEGER, TEXT, DATE, TIME, etc. To declare a variable, use the “DECLARE var_name data_type:= expression;” syntax. Variables keep the mutable data that can be modified using a function or block code. How...
[, SEND = send_function ] [, ANALYZE = analyze_function ] [, INTERNALLENGTH = { internal_length | VARIABLE } ] [, PASSEDBYVALUE ] [, ALIGNMENT = alignment ] [, STORAGE = storage ] [, DEFAULT = default ] [, ELEMENT = element ] ...