As a developer, it is really important for us to understand database design and underlying tables used in application. Sometime we do not have direct access to database server so that we can not open the server console and look in to the database.
In this case we can take help of SysObjects, SysColumns, SysTypes tables of SQL Server 2005. These tables stores the information about each tables and columns and their data types. Using this tables you can write the query to find out all the tables and columns in selected database. Below is the query that gives you all the table and columns for those tables with data types and length.
SELECT
SysObjects.[Name] as TableName,
SysColumns.[Name] as ColumnName,
SysTypes.[Name] As DataType,
SysColumns.[Length] As Length
FROM
SysObjects INNER JOIN SysColumns
ON SysObjects.[Id] = SysColumns.[Id]
INNER JOIN SysTypes
ON SysTypes.[xtype] = SysColumns.[xtype]
WHERE
SysObjects.[Type]='U'
ORDER BY
SysObjects.[Name]
“Type” columns of SysObjects table represent the different objects available in database (like Table,Trigger,Stored Procedures etc.). Below list explains the different values of “Type” columns.
C = CHECK constraint
D = Default or DEFAULT constraint
F = FOREIGN KEY constraint
FN = Scalar function
IF = Inlined table-function
K = PRIMARY KEY or UNIQUE constraint
L = Log
P = Stored procedure
R = Rule
RF = Replication filter stored procedure
S = System table
TF = Table function
TR = Trigger
U = User table
V = View
X = Extended stored procedure
For more detail refer SysObjects and SysColumns. and So in fig – (1) query uses [type] = ‘U’. This means query displays al the user tables. You can change the condition in WHERE clause to get different objects. The query shown below displays all the triggers in selected database.
SELECT
b.[Name] as [Table Name],
a.[Name] as [Trigger Name],
a.[crdate] as [Created Date]
FROM
SysObjects a INNER JOIN Sysobjects b
ON a.[parent_obj] = b.[id]
WHERE
a.[type] = 'TR'
ORDER BY
b.[Name]
Happy Programming !!!!
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