Hashtable使用哈希？(Hashing used by Hashtable?)

 您需要先根据您的查询创建一个VIEW ，然后为其添加一个全文索引，其中将包含ParentName列。 如果没有正在搜索的列上的全文索引， FREETEXT和CONTAINS都不起作用。 
 
 像这样的东西应该可以帮助你： 
 
CREATE VIEW ExpectationsView AS
SELECT ExpectationId
    ,ExpectationName
    ,(
       CASE 
          WHEN ExpectationOrganization_OrganizationId IS NOT NULL
                THEN (
                       SELECT OrganizationName
                       FROM Organizations
                       WHERE OrganizationId = ExpectationOrganization_OrganizationId
                       )
          WHEN ExpectationBeneficiary_BeneficiaryId IS NOT NULL
                THEN (
                       SELECT BeneficiaryName
                       FROM Beneficiaries
                       WHERE BeneficiaryId = ExpectationBeneficiary_BeneficiaryId
                       )
          ELSE (
                    SELECT TeamName
                    FROM Teams
                    WHERE TeamId = ExpectationTeam_TeamId
                    )
          END
       ) AS ParentName
FROM Expectations
GO

-- This index is needed for FTS index.
-- Note, I trust ExpectationId column is unique in your SELECT above,
-- if it's not, the below CREATE INDEX will fail and you will need to provide 
-- a new column to your VIEW which will uniquely identify each row, then use 
-- that PK-like column in the below index
CREATE UNIQUE CLUSTERED INDEX PK_ExpectationsView   
    ON ExpectationsView (ExpectationId);  
GO  

CREATE FULLTEXT CATALOG fts_catalog;  
GO  
CREATE FULLTEXT INDEX ON ExpectationsView  
 (
    ExpectationName Language 1033,   
    ParentName Language 1033
 )   
  KEY INDEX PK_ExpectationsView 
      ON fts_catalog;
      WITH (CHANGE_TRACKING = AUTO)
GO  
 
 一旦包含相关列的全文索引存在，您可以在查询中使用FREETEXT或CONTAINS ： 
 
SELECT ExpectationId, ExpectationName, ParentName FROM ExpectationsView
    WHERE FREETEXT(ExpectationName, @Keyword) OR FREETEXT(ParentName, @Keyword)
 
 请注意，上面提供的代码是我的头顶，因为我没有数据模式，因此无法尝试运行它。 但是，它应该给你关于如何进行的一般想法。 HTH。 

You need to create a VIEW based on your query first then add a Full-Text index to it which will include the ParentName column. Without the Full-Text index over a column being searched neither FREETEXT nor CONTAINS will work.
 
Something like that should help you:
 
CREATE VIEW ExpectationsView AS
SELECT ExpectationId
    ,ExpectationName
    ,(
       CASE 
          WHEN ExpectationOrganization_OrganizationId IS NOT NULL
                THEN (
                       SELECT OrganizationName
                       FROM Organizations
                       WHERE OrganizationId = ExpectationOrganization_OrganizationId
                       )
          WHEN ExpectationBeneficiary_BeneficiaryId IS NOT NULL
                THEN (
                       SELECT BeneficiaryName
                       FROM Beneficiaries
                       WHERE BeneficiaryId = ExpectationBeneficiary_BeneficiaryId
                       )
          ELSE (
                    SELECT TeamName
                    FROM Teams
                    WHERE TeamId = ExpectationTeam_TeamId
                    )
          END
       ) AS ParentName
FROM Expectations
GO

-- This index is needed for FTS index.
-- Note, I trust ExpectationId column is unique in your SELECT above,
-- if it's not, the below CREATE INDEX will fail and you will need to provide 
-- a new column to your VIEW which will uniquely identify each row, then use 
-- that PK-like column in the below index
CREATE UNIQUE CLUSTERED INDEX PK_ExpectationsView   
    ON ExpectationsView (ExpectationId);  
GO  

CREATE FULLTEXT CATALOG fts_catalog;  
GO  
CREATE FULLTEXT INDEX ON ExpectationsView  
 (
    ExpectationName Language 1033,   
    ParentName Language 1033
 )   
  KEY INDEX PK_ExpectationsView 
      ON fts_catalog;
      WITH (CHANGE_TRACKING = AUTO)
GO  
 
Once the Full-Text index which includes the relevant columns is there you can use FREETEXT or CONTAINS in queries:
 
SELECT ExpectationId, ExpectationName, ParentName FROM ExpectationsView
    WHERE FREETEXT(ExpectationName, @Keyword) OR FREETEXT(ParentName, @Keyword)
 
Note, the above code I've provided off the top of my head because I don't have data schema for your case so couldn't try running it. However, it should give you the general idea on how to proceed. HTH.