【本文纯个人理解,错误轻喷,非常希望能有大神指点】
linq的lambda
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生成的sql
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var queryLeft =
from t in con.TRANSSECTION_BASEPRICE
join u in con.SYS_STAFF on t.INPUT_MAN equals u.CODEUSER
into TranNew
from
tr
in TranNew.DefaultIfEmpty()
select new
{
t.DEST_PLACE,
t.IF_VALID,
t.INFO_ID,
t.INPUT_TIME,
INPUTMAN =tr==null?t.INPUT_MAN: tr.USERNAME
};
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SELECT
1 AS "C1",
"Extent1"."DEST_PLACE" AS "DEST_PLACE",
"Extent1"."IF_VALID" AS "IF_VALID",
"Extent1"."INFO_ID" AS "INFO_ID",
"Extent1"."INPUT_TIME" AS "INPUT_TIME",
CASE WHEN ("Extent2"."ID" IS NULL) THEN "Extent1"."INPUT_MAN" ELSE "Extent2"."USERNAME" END AS "C2"
FROM "JSXW"."TRANSSECTION_BASEPRICE" "Extent1"
LEFT OUTER JOIN "JSXW"."SYS_STAFF" "Extent2" ON ("Extent1"."INPUT_MAN" = "Extent2"."CODEUSER") OR (("Extent1"."INPUT_MAN" IS NULL) AND ("Extent2"."CODEUSER" IS NULL))
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var queryRight = from u in con.SYS_STAFF
join t in con.TRANSSECTION_BASEPRICE on u.CODEUSER equals t.INPUT_MAN
into unew
from un in unew.DefaultIfEmpty()
select new
{
un.DEST_PLACE,
un.IF_VALID,
un.INFO_ID,
un.INPUT_TIME,
INPUTMAN = u.USERNAME
};
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SELECT
1 AS "C1",
"Extent2"."DEST_PLACE" AS "DEST_PLACE",
"Extent2"."IF_VALID" AS "IF_VALID",
"Extent2"."INFO_ID" AS "INFO_ID",
"Extent2"."INPUT_TIME" AS "INPUT_TIME",
"Extent1"."USERNAME" AS "USERNAME"
FROM "JSXW"."SYS_STAFF" "Extent1"
LEFT OUTER JOIN "JSXW"."TRANSSECTION_BASEPRICE" "Extent2" ON ("Extent1"."CODEUSER" = "Extent2"."INPUT_MAN") OR (("Extent1"."CODEUSER" IS NULL) AND ("Extent2"."INPUT_MAN" IS NULL))
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var queryInner = from t in con.TRANSSECTION_BASEPRICE
join u in con.SYS_STAFF on t.INPUT_MAN equals u.CODEUSER
select new
{
t.DEST_PLACE,
t.IF_VALID,
t.INFO_ID,
t.INPUT_TIME,
INPUTMAN = u.USERNAME
};
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SELECT
1 AS "C1",
"Extent1"."DEST_PLACE" AS "DEST_PLACE",
"Extent1"."IF_VALID" AS "IF_VALID",
"Extent1"."INFO_ID" AS "INFO_ID",
"Extent1"."INPUT_TIME" AS "INPUT_TIME",
"Extent2"."USERNAME" AS "USERNAME"
FROM "JSXW"."TRANSSECTION_BASEPRICE" "Extent1"
INNER JOIN "JSXW"."SYS_STAFF" "Extent2" ON ("Extent1"."INPUT_MAN" = "Extent2"."CODEUSER") OR (("Extent1"."INPUT_MAN" IS NULL) AND ("Extent2"."CODEUSER" IS NULL))
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