使用具有多个别名的外部联接来联接两个SELECT语句

Question

我有一个复杂的select语句，当执行该语句时，会给它一个我想要的日期或日期范围，然后输出结果。问题是我不知道如何将相同的SQL语句与第一个具有1个日期范围的Statement和第二个具有另一个数据范围的语句联接在一起。下面的例子：

执行select语句时，我选择11月：
EMPLID名称Current_Gross_Hours（11月）

当我再次执行select语句时，我从1月到11月进行选择：
EMPLID NAME Year_To_Date_Hours（1月-11月）

我想要的是：
EMPLID名称Current_Gross_Hours（11月）Year_To_Date_Hours（1月-11月）

如果自行执行，则SQL Select语句将正确运行。但是我不知道如何加入他们。这是我要编写的SQL代码，但我不知道如何正确编写SQL语句。任何帮助或指示，我们将不胜感激。

(SELECT DISTINCT
SUM("PSA"."AL_HOURS") AS "Current Gross Hours", "PSJ"."EMPLID","PSP"."NAME"
FROM
"PS_JOB" "PSJ", "PS_EMPLOYMENT" "PSE", "PS_PERSONAL_DATA" "PSP", "PS_AL_CHK_HRS_ERN" "PSA"
WHERE
((("PSA"."CHECK_DT" = TO_DATE('2011-11-01', 'YYYY-MM-DD')) AND
("PSJ"."PAYGROUP" = 'SK2') AND
(("PSJ"."EFFSEQ"= ( 
    SELECT MAX("INNERALIAS"."EFFSEQ")
    FROM "PS_JOB" INNERALIAS 
    WHERE "INNERALIAS"."EMPL_RCD_NBR" = "PSJ"."EMPL_RCD_NBR"
    AND "INNERALIAS"."EMPLID" = "PSJ"."EMPLID"
    AND "INNERALIAS"."EFFDT" = "PSJ"."EFFDT")
AND
"PSJ"."EFFDT" = ( 
    SELECT MAX("INNERALIAS"."EFFDT")
    FROM "PS_JOB" INNERALIAS 
    WHERE "INNERALIAS"."EMPL_RCD_NBR" = "PSJ"."EMPL_RCD_NBR"
    AND "INNERALIAS"."EMPLID" = "PSJ"."EMPLID"
    AND "INNERALIAS"."EFFDT" <= SYSDATE))))) 
AND
("PSJ"."EMPLID" = "PSE"."EMPLID" ) AND ("PSJ"."EMPLID" = "PSP"."EMPLID" ) AND ("PSJ"."FILE_NBR" = "PSA"."FILE_NBR" ) AND ("PSJ"."PAYGROUP" = "PSA"."PAYGROUP" ) AND ("PSE"."EMPLID" = "PSP"."EMPLID" )
GROUP BY
"PSJ"."EMPLID", "PSP"."NAME"
) AS "Q1"

LEFT JOIN


(SELECT DISTINCT
SUM("PSA"."AL_HOURS") AS "YEAR_TO_DATE Gross Hours", "PSJ"."EMPLID"
FROM
"PS_JOB" "PSJ", "PS_EMPLOYMENT" "PSE", "PS_PERSONAL_DATA" "PSP", "PS_AL_CHK_HRS_ERN" "PSA"
WHERE
((("PSA"."CHECK_DT" BETWEEN TO_DATE('2011-01-01', 'YYYY-MM-DD') AND TO_DATE('2011-11-01', 'YYYY-MM-DD'))  AND
("PSJ"."PAYGROUP" = 'SK2') AND
(("PSJ"."EFFSEQ"= ( 
    SELECT MAX("INNERALIAS"."EFFSEQ")
    FROM "PS_JOB" INNERALIAS 
    WHERE "INNERALIAS"."EMPL_RCD_NBR" = "PSJ"."EMPL_RCD_NBR"
    AND "INNERALIAS"."EMPLID" = "PSJ"."EMPLID"
    AND "INNERALIAS"."EFFDT" = "PSJ"."EFFDT")
AND
"PSJ"."EFFDT" = ( 
    SELECT MAX("INNERALIAS"."EFFDT")
    FROM "PS_JOB" INNERALIAS 
    WHERE "INNERALIAS"."EMPL_RCD_NBR" = "PSJ"."EMPL_RCD_NBR"
    AND "INNERALIAS"."EMPLID" = "PSJ"."EMPLID"
    AND "INNERALIAS"."EFFDT" <= SYSDATE))))) 
AND
("PSJ"."EMPLID" = "PSE"."EMPLID" ) AND ("PSJ"."EMPLID" = "PSP"."EMPLID" ) AND ("PSJ"."FILE_NBR" = "PSA"."FILE_NBR" ) AND ("PSJ"."PAYGROUP" = "PSA"."PAYGROUP" ) AND ("PSE"."EMPLID" = "PSP"."EMPLID" )
GROUP BY
"PSJ"."EMPLID"
) AS "Q2"
 ON "Q1"."EMPLID"="Q2"."EMPLID"
ORDER BY
"Q1"."NAME"

Answer 1

您一SELECT ... FROM开始缺少。该AS关键字仅在创建列别名时有效，而在查询块别名中无效。引号仅对于区分大小写的列名是必需的-在您的示例中看起来并不正确，但它们经常会引起错误。

SELECT Q1.NAME, ...
FROM
(
     SELECT ...
) Q1
JOIN
(
     SELECT ...
) Q2
ON Q1.EMPLID=Q2.EMPLID
ORDER BY Q1.NAME