To retrieve a list of all servers registered on the instance:

EXEC sp_helpserver;

sp_who2

This procedure can be used to find information on current SQL server sessions. Since it is a procedure, it's often helpful to store the results into a temporary table or table variable so one can order, filter, and transform the results as needed.

The below can be used for a queryable version of sp_who2:

-- Create a variable table to hold the results of sp_who2 for querying purposes

DECLARE @who2 TABLE (
      SPID INT NULL,
      Status VARCHAR(1000) NULL,
      Login SYSNAME NULL,
      HostName SYSNAME NULL,
      BlkBy SYSNAME NULL,
      DBName SYSNAME NULL,
      Command VARCHAR(8000) NULL,
      CPUTime INT NULL,
      DiskIO INT NULL,
      LastBatch VARCHAR(250) NULL,
      ProgramName VARCHAR(250) NULL,
      SPID2 INT NULL, -- a second SPID for some reason...?
      REQUESTID INT NULL
)

INSERT INTO @who2
EXEC sp_who2

SELECT    *
FROM    @who2 w
WHERE    1=1

Examples:

-- Find specific user sessions:
SELECT  *
FROM    @who2 w
WHERE   1=1
    and  login = 'userName'

-- Find longest CPUTime queries:
SELECT  top 5 *
FROM    @who2 w
WHERE   1=1
order   by CPUTime desc

SELECT    SERVERPROPERTY('ProductVersion') AS ProductVersion,  
          SERVERPROPERTY('ProductLevel') AS ProductLevel,  
          SERVERPROPERTY('Edition') AS Edition,  
          SERVERPROPERTY('EngineEdition') AS EngineEdition;  

SELECT  DATEDIFF(DAY, login_time, getdate()) UpDays
FROM    master..sysprocesses 
WHERE   spid = 1

To discover SQL Server's edition, product level and version number as well as the host machine name and the server type:

SELECT    SERVERPROPERTY('MachineName') AS Host,
          SERVERPROPERTY('InstanceName') AS Instance,
          DB_NAME() AS DatabaseContext,
          SERVERPROPERTY('Edition') AS Edition, 
          SERVERPROPERTY('ProductLevel') AS ProductLevel, 
          CASE SERVERPROPERTY('IsClustered') 
            WHEN 1 THEN 'CLUSTERED' 
            ELSE 'STANDALONE' END AS ServerType,
          @@VERSION AS VersionNumber;

Query to search last executed sp's in db

SELECT execquery.last_execution_time AS [Date Time], execsql.text AS [Script]
FROM sys.dm_exec_query_stats AS execquery
CROSS APPLY sys.dm_exec_sql_text(execquery.sql_handle) AS execsql
ORDER BY execquery.last_execution_time DESC

Query to search through Stored procedures

SELECT o.type_desc AS ROUTINE_TYPE,o.[name] AS ROUTINE_NAME,
m.definition AS ROUTINE_DEFINITION
FROM sys.sql_modules AS m INNER JOIN sys.objects AS o
ON m.object_id = o.object_id WHERE m.definition LIKE '%Keyword%'
order by ROUTINE_NAME

Query to Find Column From All Tables of Database

SELECT t.name AS table_name,
SCHEMA_NAME(schema_id) AS schema_name,
c.name AS column_name
FROM sys.tables AS t
INNER JOIN sys.columns c ON t.OBJECT_ID = c.OBJECT_ID
where c.name like 'Keyword%'
ORDER BY schema_name, table_name;

Query to to check restore details

WITH LastRestores AS
(
SELECT
    DatabaseName = [d].[name] ,
    [d].[create_date] ,
    [d].[compatibility_level] ,
    [d].[collation_name] ,
    r.*,
    RowNum = ROW_NUMBER() OVER (PARTITION BY d.Name ORDER BY r.[restore_date] DESC)
FROM master.sys.databases d
LEFT OUTER JOIN msdb.dbo.[restorehistory] r ON r.[destination_database_name] = d.Name
)
SELECT *
FROM [LastRestores]
WHERE [RowNum] = 1

Query to to find the log

select top 100 * from databaselog
Order by Posttime desc

Query to to check the Sps details

SELECT name, create_date, modify_date
FROM sys.objects
WHERE type = 'P'
Order by modify_date desc