postgresql - PostgreSQL Syntax error in PGAdmin

Question

I am new to PostgreSQL and am using the query tool in PGAdmin. I'm trying to run pgsql queries that use variables, but I can't seem to get the syntax right.

Here's a sample query that gives a syntax error:

DECLARE
  num INTEGER;

BEGIN

  num := 3;
  PRINT num;

END;

---

Update:
Ok, let me try and explain. I come from a SQL server background. In the management studio, I can open a query window and play with (T)-SQL queries.

For example, I can write something like this:

DECLARE @num INT
SET @num = 3
SELECT @num

I know this is a dumb example, but I'm just trying to declare a variable and do something with it. I'm trying to familiarise myself with PL/PGSQL.

---

Update, again:
It's me again. I'm trying the script below and get a "[ERROR ] 7.0-2: syntax error, unexpected character". Is this meant to work in PGAdmin?

DECLARE
  num INTEGER;

BEGIN

  num := 3;
  RAISE NOTICE '%', num;

END;

Answer 1

您可以使用 do 语句。例如：

do $$
declare 
  num integer := 10;
begin

    RAISE INFO 'VARIABLE: %', num;

end;
$$language plpgsql;

当您使用 pgadmin 时，您必须使用按钮 EXECUTE QUERY 而不是 Execute pdScript，如下所述：

http://postgresql.1045698.n5.nabble.com/PgAmin3-Anonymous-code-block-can-t-be-executed-by-pressing-quot-Execute-PG-script-quot-button-td5771073.html

do 语句的文档在这里：

http://www.postgresql.org/docs/9.3/static/sql-do.html

Answer 2

只是为了改写和“具体化”其他人所说的话：PostgreSQL 中没有内联过程。也没有 PRINT 语句。你必须：

CREATE OR REPLACE FUNCTION test() RETURNS void AS $$
DECLARE
  num INTEGER;

BEGIN

  num := 3;
  RAISE NOTICE '%', num;

END;
$$ LANGUAGE plpgsql;

SELECT test();

Answer 3

If you're trying to print out num (say, for debugging), you could try:

RAISE NOTICE '%', num;

http://www.postgresql.org/docs/8.4/static/plpgsql-errors-and-messages.html

PRINT doesn't mean anything in PL/pgSQL.

Answer 4

Postgres 本身不支持类似的东西（但）。psql（官方命令行客户端）有一些基本的脚本。

对您来说最好的选择是 pgAdmin，它已经内置了脚本。

Answer 5

我不知道你想达到什么目的。PostgreSQL 不支持这种语法。类似的关键字（除了 PRINT？！）在 PL/pgSQL 中，它是用于构建 FUNCTIONS 的过程语言，而不是用于编写独立的 SQL 查询。