... BY CompanyName";
// Retrieve the plan into DataReader.
SqlDataReader dr = cmd.ExecuteReader( );
// Iterate over all result sets and all rows to get plan.
do
{
while (dr.Read( )) ... SHOWPLAN_TEXT (from the Query Execution category) is ON, SQLServer
returns a result set containing detailed information about how the SQL statements are
going to be executed rather than actually ... the plan. For batch
SQL statements, the result sets alternate between statement and plan for each statement in
the batch.
SHOWPLAN_TEXT does not need to be explicitly set to OFF. It only affects...
... Team LiB ]
Recipe 10.9 GettingaSQLServerQueryPlan
Problem
You need to retrieve information about how query statements are executed by the SQL
Server.
Solution
Use the SET SHOWPLAN_TEXT ... the plan for.
cmd.CommandText = "SELECT * FROM Customers WHERE Country='USA' " +
"ORDER BY CompanyName";
// Retrieve the plan into DataReader.
SqlDataReader ... Create and execute the command to retrieve the plan.
SqlCommand cmd = new SqlCommand("SET SHOWPLAN_TEXT ON", conn);
conn.Open( );
cmd.ExecuteNonQuery( );
// Create the command...
... string is passed to a DataAdapter control, filling a data table. The
data is then displayed when the data source of the DataGrid control is set to the data
table.
Comments
You can enhance this ... the txtSQLString text and create a data table; then set the
' data source of the data grid.
odaDisplay = New OleDb.OleDbDataAdapter(Me.txtSQLString.Text,
mcnn)
odaDisplay.Fill(dtDisplay) ... btnView_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles btnView.Click
Dim odaDisplay As OleDb.OleDbDataAdapter
Dim dtDisplay As New DataTable()
Try
' Take...
... AuthID First Name Last Name
A1
John Brown
A2
Matthew Bortniker
A3
Rick Johnson
A4
Peter Wright
A5
James Moon
AuthorBook
BookID
AuthID
1 A1
2 A2
2 A3
3 A4
3 A5
3 A1
Ngoài ra một trong ... and jobs).
Cấu Trúc Vật Lý C a Một SQLServer Database
Mỗi một database trong SQLServer đều ch a ít nhất một data file chính
(primary), có thể có thêm một hay nhiều data file phụ (Secondary) ... động lại
SQL Server hay khi ta disconnect.
• Model : Database này đóng vai trò như một bảng kẻm (template) cho các
database khác. Ngh a là khi một user database được tạo ra thì SQLServer
sẽ...
... (template) cho các database
khác. Ngh a là khi một user database được tạo ra thì SQLServer sẽ copy toàn bộ các
system objects (tables, stored procedures ) từ Model database sang database mới
v a ... (SQL) Server nào đó là ta nói đến một Instance c a
SQLServer 2000, thông thường đó là Default Instance. Một Instance c aSQLServer 2000
có 4 system databases và một hay nhiều user database. ...
Sp_help ['object']
Cung cấp thông tin về một database object (table, view )
hay một data type.
Sp_helpdb ['database'] Cung cấp thông tin về một database cụ thể nào đó.
Sau đó...
... command.
SqlCommand cmd = new SqlCommand(sqlText, conn, tran);
// Create the DataAdapter and CommandBuilder.
SqlDataAdapter da = new SqlDataAdapter(cmd);
SqlCommandBuilder cb = new SqlCommandBuilder(da); ... being read by a user and preventing users from reading data being changed by a
user. Locks are acquired and released by user actions; they are managed internally by
database software.
A locking ... statement.
READCOMMITTED
Use the same locking as a transaction with an isolation level
of READ COMMITTED.
READUNCOMMITTED Same as NOLOCK.
REPEATABLEREAD
Use the same locking as a transaction...
...
mySqlConnection.ConnectionString = server= localhost;database=Northwind;uid=sa;
mySqlConnection.ConnectionTimeout = 15
mySqlConnection.Database = Northwind
mySqlConnection.DataSource = localhost
mySqlConnection.PacketSize ... when there's a suitable connection
already available. When you close a connection, that connection isn't actually closed;
instead, your connection is marked as unused and stored in ... stores database connections in a pool. Connection
pooling offers a great performance improvement because you don't have to wait for a
brand new connection to the database to be established...
...
[ Team LiB ]
Recipe 9.8 Debugging aSQLServer Stored Procedure
Problem
Given an application that uses aSQLServer stored procedure that is causing errors, you
need ...
Use Visual Studio .NET to debug SQLServer stored procedures (in both standalone
mode and from managed code).
Discussion
Debugging a stored procedure in standalone mode
You can debug a stored ...
2. Create a connection to the database or select an existing connection.
3. Select and expand the node for the database that contains the stored procedure.
4. Expand the Stored Procedures node....
... that handles an event is known as an event handler. You call this method
when a particular event is fired. All event handler methods must return void and accept
two parameters. The first parameter ... // create a SqlCommand object
SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
// run a PRINT statement
mySqlCommand.CommandText =
"PRINT 'This is the message from ... SqlConnection(" ;server= localhost;database=Northwind;uid=sa;pwd=sa");
// monitor the StateChange event using the StateChangeHandler() method
mySqlConnection.StateChange +=
new StateChangeEventHandler(StateChangeHandler);...
... command.
SqlCommand cmd = new SqlCommand(sqlText, conn, tran);
// Create the DataAdapter and CommandBuilder.
SqlDataAdapter da = new SqlDataAdapter(cmd);
SqlCommandBuilder cb = new SqlCommandBuilder(da); ... as a transaction with an isolation level
of READ COMMITTED.
READUNCOMMITTED Same as NOLOCK.
REPEATABLEREAD
Use the same locking as a transaction with an isolation level
of REPEATABLE READ. ... SqlCommandBuilder(da);
// Fill table using the DataAdapter.
DataTable dt = new DataTable( );
da.Fill(dt);
// Bind the default view of the table to the grid.
dataGrid.DataSource = dt.DefaultView;...
... use the ADO Command object, as well as
the Parameter object if you are passing parameters.
You will create a Command object and supply the command text, which in this case will
be the name of ... Command object you are creating-in this case by using
the type of ADODB.CommandTypeEnum.adCmdStoredProc.
The next step is to create a parameter that the Command object will use. This parameter ... basCommandExamples.vb: Calling a Stored Procedure By Using
Parameters
Sub UseAStoredProcedureWithAParameter(ByVal txtResults As TextBox)
Dim cnn As New ADODB.Connection()
Dim rstCurr As New ADODB.Recordset()...
... Create the connection.
SqlConnection conn = new SqlConnection(
ConfigurationSettings.AppSettings[" ;Sql_ ConnectString"]);
// Create DataAdapter.
SqlDataAdapter da = new SqlDataAdapter(sqlText, ... DataSet.
DataSet ds = new DataSet( );
// Fill the schema and data.
da.FillSchema(ds, SchemaType.Mapped);
da.Fill(ds);
// Iterate over the table collection in the DataSet.
foreach(DataTable ... Microsoft SQL
Server Books Online.
The GetSchemaTable( ) method of the DataReader also returns all column lengths. The
method returns a DataTable containing column metadata for a DataReader, where...
... the DataSet passed in
as an NText input parameter @data. The parameters @data and @datadeleted
contain an XML representation of a DataSet containing all updated and added
records and all deleted ... System.EventArgs e)
{
ds = new DataSet( );
// Create the DataAdapter.
SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM " + TABLENAME,
ConfigurationSettings.AppSettings[" ;Sql_ ConnectString"]); ... Load the schema and data for the table.
da.FillSchema(ds, SchemaType.Source, TABLENAME);
da.Fill(ds, TABLENAME);
// Columns in XML representation of data as attributes
foreach(DataColumn...
...
ListBox Name lstDatabases
Label Name Label3
Text Backup Devices
ListBox Name lstBackupDevices
Command Button Name btnBackup
Text &Backup
Label Name Label4
Text Backup Set Name
TextBox ... into a List Box
Private Sub frmHowTo7_2_Load(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles MyBase.Load
' Load up the SQL Servers
LoadSQLServers(Me.lstSQLServers) ... the SQLServer that he wants to display the
databases of. He can then choose the database and backup device. From there, the user
can click the Backup button to perform the backup. You can then...
... name Data type Description
CONSTRAINT_CATALOG nvarchar(128) Constraint name
CONSTRAINT_SCHEMA nvarchar(128) Constraint owner
CONSTRAINT_NAME sysname Constraint name
TABLE_CATALOG nvarchar(128) ... REFERENTIAL_CONSTRAINTS information schema view
Column name Data type Description
CONSTRAINT_CATALOG nvarchar(128) Database name
CONSTRAINT_SCHEMA nvarchar(128) Constraint owner name
CONSTRAINT_NAME ...
CONSTRAINT_CATALOG nvarchar(128) Constraint qualifier
CONSTRAINT_SCHEMA nvarchar(128) Constraint owner name
CONSTRAINT_NAME nvarchar(128) Constraint name
TABLE_CATALOG nvarchar(128) Table qualifier
TABLE_SCHEMA...