How is table populated in SQL Server - sql-server

My company has a table in a db, which is populated with some store numbers. It's updated daily with data for the past 30 days (running window). The table was set up by someone who's no longer at the company.
My question is, how to find out where the data comes from? I.e. what populates the table and how?
I've tried right-clicking on the table and clicking "View Dependencies" in SSMS, but it doesn't list anything.
I need to find out where the data comes from, since the table has started to show considerably fewer observations than before.
The server is running SQL Server version 13 and I'm using SSMS 18.

Run the query below, it will tell you if your table is used in any function, procedure, trigger or view on the database.
Then you can run the same query again on the found objects off course.
SELECT DISTINCT
o.name AS Object_Name,
o.type_desc,
m.*
FROM sys.sql_modules m
INNER JOIN sys.objects o ON m.object_id = o.object_id
WHERE m.definition Like '%YOUR_TABLE_NAME%'
This will only tell you if this table name is used in any object on your database, not if its used from any application.
But at least it will tell you any function/procedure names that you need to look for in your applications

Related

Running the following query to view a list of all tables and views that are feeding into my Store Procedure, but only pulling from selected database

I'm fairly new to SQL, and I'm trying to automate my process of viewing all of the tables (from multiple databases) that feed into a specific proc. When I run the below query, I am only getting results from one database, but I know that this SP pulls from 3+ databases. Any suggestions or entirely new ways of going about this?
SELECT
NAME as 'List Of Tables'
FROM SYSOBJECTS
WHERE ID IN ( SELECT SD.DEPID
FROM SYSOBJECTS SO,
SYSDEPENDS SD
WHERE SO.NAME = 'X-Table-Name'
AND SD.ID = SO.ID
)

Is there a way to identify if a column is not been used in a SQL Server Database?

I have a big database and a lot tables and I would like to identify what columns are not been called by any store procedure or any query, or not in use.
I'm not sure if this is what you're looking for, but in your DB under views there's a folder for System Views - three of which are the following. Looking in all_objects look for the table name, then use the object_id of that table to select from the other queries. There may be other meta-data here that is appropriate for your need.
SELECT *
FROM sys.all_objects
SELECT *
FROM sys.all_columns
WHERE object_id = 981578535
SELECT *
FROM sys.all_views
WHERE object_id = 981578535
After an investigation I have found a new feature of SQL Server called Query Store where you can find in disk the executions with other information. If you have a SQL Server 2016 instance you can find it in the properties of the data base. There you can change the amount of days to capture and then you can in theory try to find the columns in question. The idea of this technology is to give you more options for performance tuning.
You can find the information with this query :
SELECT TOP 10 qt.query_sql_text, q.query_id,
qt.query_text_id, p.plan_id, rs.last_execution_time
FROM sys.query_store_query_text AS qt
JOIN sys.query_store_query AS q
ON qt.query_text_id = q.query_text_id
JOIN sys.query_store_plan AS p
ON q.query_id = p.query_id
JOIN sys.query_store_runtime_stats AS rs
ON p.plan_id = rs.plan_id
where qt.query_sql_text LIKE '%ColumnToFind%'
ORDER BY rs.last_execution_time;
Credits: Query Store

Find dependencies between tables in sql database

I have a Sql database with data. I have been asked to populate a fresh identical database with all the required master data so that the application is able to up and run for a new customer.
First approach
Delete all the data from database, run the application, sure i won't be even able to login. Observe errors, identify tables which need master data(sure User table at least), insert data. Then assume i am going to access a module. But without some master data it'll give me errors. Observe errors, identify tables which need master data, insert data.
But this seems not practical.
Second approach
While keeping the data in database, take one table at a time, using queries or sql server management studio tools, find all dependent tables. Keep the parent table data and delete child table data. Do this for all tables. In second round consider the remaining parent tables. Some table's data are inserted from application. Identify those and delete them. This way i can have relevant master data at the end. But i don't know how to approach this.
All these are my thoughts. Sure there might be many more approaches which are more precise and easier than these.I am confused with what to do. Please guide me. Thanks!
Here's a few queries you could use to figure out which table and column is referencing which table and column...
select * from INFORMATION_SCHEMA.KEY_COLUMN_USAGE
select * from INFORMATION_SCHEMA.columns
select * from INFORMATION_SCHEMA.tables
select * from sys.foreign_keys
select * from sys.foreign_key_columns
select * from [sys].[objects] where [name] = 'your_tablename'
For more, open Object Explorer (View Menu) and expand:
Databases/System Databases/Master/Views/System Views.
Also, check out any database diagrams there might be in Object Explorer:
Databases/Your_db_name/Database Diagrams.
How big is the database ?
No matter what you have to make proper documentation ?So better start with documentation.
You have to list all table one by one and identity if it is master table.
Remember the diff. between Delete or Truncate.
While doucmenting above query will come in handy.
Save the query and document for future need.
Most importantly,there should not be any error,even if any of the table is empty.
To find foreign key dependecies between tables you can use
SELECT FKT.name 'Parent table', CHT.name 'Child table' FROM sys.foreign_keys FK
JOIN sys.tables CHT ON FK.parent_object_id = CHT.object_id
JOIN sys.tables FKT ON FK.referenced_object_id = FKT.object_id
There is also ways to find dependencies in database views using system views.

Finding a referenced table in multiple views using SQL

I have a huge database with 50+ Views, Tables and Stored Procedures. I want to run a search to find I specific piece of text, i.e a table name, to see if it is being referenced anywhere.
I originally tried a C# route but I am suspecting this will be easier in SQL. The logic I am thinking about is possibly creating a query that loops through all Tables, Views and Stored Procedures and returns the data if it is available.
Any ideas?
In the below query, instead of the matchingstring replace your tablename, it will returns list of objects related to the search string
SELECT DISTINCT SO.[name]
FROM sysobjects SO
JOIN syscomments SC ON SC.Id = SO.Id
WHERE SC.[text] LIKE '%matchingstring%'
SELECT object_name(id) FROM sys.syscomments WHERE text LIKE'%yourtablename%'

sql server: looking for table usage through out database

How would I figure out what type of sql code such as procs, functions, views etc. are interacting with my table called TABLE1 through out a given database. Sample code would be very helpful for me.
thanks
select so.name, so.xtype
from sysobjects so (nolock)
inner join syscomments sc (nolock) on sc.id = so.id
where sc.text like '%tablename%'
This code will search all SQL Server objects for a reference to your table. You have to run this query for each database.
If a stored procedure uses your table it will appear in this query. The same is true of functions, views, and triggers.
xtype tells you the type of object.
Here are the possible xtype values:
D = Field names
F = Foreign Key
FN = Function
P = Stored Procedures
PK = Primary Key
S = System Tables
U = User tables
V = Hidden tables
Not enough info in your question, but one thing you can do is use SQL Profiler to profile where INSERTs, UPDATEs, and DELETEs are coming from.
I assume you are talking about how an app is interacting with data and what name (of say a sproc) is doing the insert / update / delete.
Look at SQL Profiler, it comes with your client tools install. Filter it to only show connections to your database (either db name or ID).
If you've been good and created your SPs/views/functions after your table was created, sp_depends will tell you evertyhing referencing the table. Exept for dynamic sql that is.

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