Netezza/SQL列别名连接具有参数值的文本

Question

在下面的存储过程中，我只想创建一个基于参数值的列别名。看起来很简单，但我找不到答案。

CREATE OR REPLACE PROCEDURE "SP"(INTEGER, INTEGER)
RETURNS INTEGER
EXECUTE AS OWNER
LANGUAGE NZPLSQL AS
BEGIN_PROC
DECLARE
    whichyear ALIAS FOR $1;

BEGIN
    Select  x as "Some Text" + whichyear  from some table...

 ;
END;
END_PROC;

Answer 1

选项卡是正确的，这将需要动态SQL在Netezza。下面是一个例子。

CREATE OR REPLACE PROCEDURE "SP"(INTEGER)
RETURNS INTEGER
EXECUTE AS OWNER
LANGUAGE NZPLSQL AS
BEGIN_PROC
DECLARE
    whichyear ALIAS FOR $1;
    vSQL varchar(30000);

BEGIN
    drop table the_results if exists;

    vSQL := 'CREATE TABLE THE_RESULTS AS SELECT COL1 "SOME TEXT ' || whichyear || '" FROM TABLE_A;';

    execute immediate vSQL;

END;
END_PROC;

这是输出。

TESTDB.ADMIN(ADMIN)=> exec SP(5);
 SP
----

(1 row)

TESTDB.ADMIN(ADMIN)=> select * from the_results;
 SOME TEXT 5
-------------
           2
           3
           1
(3 rows)

Answer 2

在Server中，可以使用如下所示的动态SQL：

DECLARE @sql varchar(max) = 'Select  x as SomeText' + @whichyear + ' from sometable';

EXEC(@sql);