Find Column dependency

Question

How to find objects which depend on particular column of table.

Ex:

Table: SomeTable

Cols: col1 pk, col2, col3

I want to find all the objects which are dependent on col1 (Pk)

Answer 1

@NoFuchsGavin's script usually works great but has some limitations due to issues with sysdepends (see this blog post by Pinal Dave for an example where this gives incorrect results).

Microsoft also suggest that you avoid using sysdepends in new development work.

We can therefore use sys.dm_sql_referencing_entities and sys.dm_sql_referenced_entities as suggested here.

However I've noticed that this sometimes excludes column references due to referenced_minor_name being NULL. I've therefore added another condition which can introduce false positives but ensures that column references are not omitted from the result set.

DECLARE @SchemaName sysname = '{0}';
DECLARE @TableName sysname  = '{1}';
DECLARE @ColumnName sysname = '{2}';

SELECT
    @SchemaName + '.' + @TableName                                      AS [USED_OBJECT],
    @ColumnName                                                         AS [COLUMN],
    referencing.referencing_schema_name + '.' + referencing_entity_name AS USAGE_OBJECT,
    CASE so.type
        WHEN 'C' THEN 'CHECK constraint'
        WHEN 'D' THEN 'Default'
        WHEN 'F' THEN 'FOREIGN KEY'
        WHEN 'FN' THEN 'Scalar function' 
        WHEN 'IF' THEN 'In-lined table-function'
        WHEN 'K' THEN 'PRIMARY KEY'
        WHEN 'L' THEN 'Log'
        WHEN 'P' THEN 'Stored procedure'
        WHEN 'R' THEN 'Rule'
        WHEN 'RF' THEN 'Replication filter stored procedure'
        WHEN 'S' THEN 'System table'
        WHEN 'SP' THEN 'Security policy'
        WHEN 'TF' THEN 'Table function'
        WHEN 'TR' THEN 'Trigger'
        WHEN 'U' THEN 'User table' 
        WHEN 'V' THEN 'View' 
        WHEN 'X' THEN 'Extended stored procedure'
    END                                             AS USAGE_OBJECTTYPE,
    so.[type]                                       AS USAGE_OBJECTTYPEID
FROM sys.dm_sql_referencing_entities
    (
        @SchemaName + '.' + @TableName,
        'object'
    ) referencing
    INNER JOIN sys.objects so 
        ON referencing.referencing_id = so.object_id
WHERE
    EXISTS
    (
        SELECT
            *
        FROM
            sys.dm_sql_referenced_entities
            (
                referencing_schema_name + '.' + referencing_entity_name,
                'object'
            ) referenced
        WHERE
            referenced_entity_name = @TableName
            AND 
            (
                referenced.referenced_minor_name LIKE @ColumnName   
                -- referenced_minor_name is sometimes NULL
                -- therefore add below condition (can introduce False Positives)
                OR
                (
                    referenced.referenced_minor_name IS NULL 
                    AND 
                    OBJECT_DEFINITION
                    (
                         OBJECT_ID(referencing_schema_name + '.' + referencing_entity_name)
                    ) LIKE '%' + @ColumnName + '%'
                )
            )
    )
ORDER BY
    USAGE_OBJECTTYPE,
    USAGE_OBJECT

Above script is based on @NoFuchsGavin's answer and this blog post.

I'm interested to know if anyone has managed to find a better way which does not introduce false negatives or positives.

Answer 2

Try this query, it will get you some results that i think you are looking for.
To filter, search for the value in the c1.name or c2.name column.
To look for all the references to a certain column, use the c2.name for the column name and the OBJECT_NAME(k.referenced_object_id) as the table which holds the c2 column :)

Good Luck!

    select  OBJECT_NAME(k.parent_object_id) as parentTable
          , c1.name as parentColumn
          , OBJECT_NAME(k.referenced_object_id) as referencedTable
          , c2.name as referencedColumn
    from    sys.foreign_keys k
            inner join sys.foreign_key_columns f
              on  f.parent_object_id = k.parent_object_id
              and f.constraint_object_id = k.object_id
            inner join sys.columns c1
              on  c1.column_id = f.parent_column_id
              and c1.object_id = k.parent_object_id
            inner join sys.columns c2
              on  c2.column_id = f.referenced_column_id
              and c2.object_id = k.referenced_object_id
    where   c2.name = 'Column'
    and     OBJECT_NAME(k.referenced_object_id) = 'Table'

Answer 3

This should work!

        -- Search in All Objects
SELECT OBJECT_NAME(OBJECT_ID),definition
FROM sys.sql_modules
WHERE definition LIKE '%' + 'ColumnToBeSearched' + '%'
Order by OBJECT_NAME(OBJECT_ID)
GO

-- Search in Stored Procedure Only
SELECT DISTINCT OBJECT_NAME(OBJECT_ID),
object_definition(OBJECT_ID)
FROM sys.Procedures
WHERE object_definition(OBJECT_ID) LIKE '%' + 'ColumnToBeSearched' + '%'
GO

Answer 4

Simply Replace {0} and {1}!

declare @tbl_nme as varchar(50)
declare @col_nme as varchar(50)
declare @level int
set @level = 1
set @tbl_nme= '{0}' --TableName 
set @col_nme= '{1}' --ColumnName 



select 
  obj.name as obj_nm
, col.name as col_nm
, depobj.name as dep_obj_nm
, CASE depobj.type
     WHEN 'C' THEN 'CHECK constraint'
     WHEN 'D' THEN 'Default'
     WHEN 'F' THEN 'FOREIGN KEY'
     WHEN 'FN' THEN 'Scalar function' 
     WHEN 'IF' THEN 'In-lined table-function'
     WHEN 'K' THEN 'PRIMARY KEY'
     WHEN 'L' THEN 'Log'
     WHEN 'P' THEN 'Stored procedure'
     WHEN 'R' THEN 'Rule'
     WHEN 'RF' THEN 'Replication filter stored procedure'
     WHEN 'S' THEN 'System table'
     WHEN 'TF' THEN 'Table function'
     WHEN 'TR' THEN 'Trigger'
     WHEN 'U' THEN 'User table' 
     WHEN 'V' THEN 'View' 
     WHEN 'X' THEN 'Extended stored procedure'
  END as dep_obj_type 
, null as dep_col_nm
, depobj.type as dep_obj_typeID
, @level as level
into #temp
from   sysobjects obj 
   join   syscolumns col on obj.id = col.id 
   left   join (sysdepends dep join sysobjects depobj on depobj.id = dep.id) 
         on obj.id = dep.depid 
        and col.colid = dep.depnumber 
where  obj.name = @tbl_nme
   and col.name = @col_nme


while (@@rowcount > 0)
begin
set @level = @level + 1
insert into #temp
select 
  obj.name as obj_nm
, col.name as col_nm
, depobj.name as dep_obj_nm
, CASE depobj.type
     WHEN 'C' THEN 'CHECK constraint'
     WHEN 'D' THEN 'Default'
     WHEN 'F' THEN 'FOREIGN KEY'
     WHEN 'FN' THEN 'Scalar function' 
     WHEN 'IF' THEN 'In-lined table-function'
     WHEN 'K' THEN 'PRIMARY KEY'
     WHEN 'L' THEN 'Log'
     WHEN 'P' THEN 'Stored procedure'
     WHEN 'R' THEN 'Rule'
     WHEN 'RF' THEN 'Replication filter stored procedure'
     WHEN 'S' THEN 'System table'
     WHEN 'TF' THEN 'Table function'
     WHEN 'TR' THEN 'Trigger'
     WHEN 'U' THEN 'User table' 
     WHEN 'V' THEN 'View' 
     WHEN 'X' THEN 'Extended stored procedure'
  END as dep_obj_type 
, null as dep_col_nm
, depobj.type as dep_obj_typeID
, @level as level
from   sysobjects obj 
   join   syscolumns col on obj.id = col.id 
   left   join (sysdepends dep join sysobjects depobj on depobj.id = dep.id) 
         on obj.id = dep.depid 
        and col.colid = dep.depnumber 
where  exists(select 1 from #temp a where obj.name = a.dep_obj_nm and 
col.name = a.dep_col_nm and level = @level - 1 and dep_col_nm is not null)
end

select 
   obj_nm AS 'TABLE',
   col_nm AS 'COLUMN',
   dep_obj_nm AS 'USAGE_OBJECT',
   dep_obj_type AS 'USAGE_OBJECTTYPE',
   dep_obj_typeID AS 'USAGE_OBJECTTYPEID'
from #temp
drop table #temp

Answer 5

The sql provided in the accepted answer above should include an additional join condition between sys.foreign_keys and sys.foreign_key_columns. See line beginning with "and" below:

from    sys.foreign_keys k
        inner join sys.foreign_key_columns f
          on  f.parent_object_id = k.parent_object_id
               and f.constraint_object_id = k.object_id

For reference, here's the whole script with the amended join:

select  OBJECT_NAME(k.parent_object_id) as parentTable
        , c1.name as parentColumn
        , OBJECT_NAME(k.referenced_object_id) as referencedTable
        , c2.name as referencedColumn
from    sys.foreign_keys k
        inner join sys.foreign_key_columns f
            on  f.parent_object_id = k.parent_object_id
            and f.constraint_object_id = k.object_id
        inner join sys.columns c1
            on  c1.column_id = f.parent_column_id
            and c1.object_id = k.parent_object_id
        inner join sys.columns c2
            on  c2.column_id = f.referenced_column_id
            and c2.object_id = k.referenced_object_id
where   c2.name = 'GUID'
and     OBJECT_NAME(k.referenced_object_id) = 'AuthDomain'

Answer 6

Try This: This will give all the object names which are referencing Pk of your table.

select  OBJECT_NAME(parent_object_id) from sys.foreign_keys where referenced_object_id = OBJECT_ID('YourTableName')

Answer 7

Find specific column dependencies

SELECT OBJECT_NAME(referencing_id),
    referenced_database_name,
    referenced_schema_name,
    referenced_entity_name
FROM sys.sql_expression_dependencies
WHERE OBJECT_NAME(referenced_id) = 'table_name'
    AND OBJECT_DEFINITION(referencing_id) LIKE '%field_name%';