saving dynamic dataset to sql ce

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G

Guest

I am getting a dataset returned from a web service call, I want to persist
this in sql ce. Is there an easy way of doing this?
 
One line solution - no. Easy to implement solution - yes.

For each table in DataSet enumerate columns in it, construct and execute
"Create Table" statement.
Enumerate and add relations. Construct and execute insert statements.
You're done.

Best regards,

Ilya

This posting is provided "AS IS" with no warranties, and confers no rights.

--------------------
 
Here is some code you might find helpful.

It contains some helper functions for storing a dataset to SqlCe and also
restoring a dataset from a SqlCe database

class manipulateSQLCE
{
public static string GetSQLTypeName (Type t) {

if (t == typeof(SByte)) return "TinyInt";
if (t == typeof(Int16)) return "SmallInt";
if (t == typeof(Int32)) return "Int";
if (t == typeof(Int64)) return "BigInt";
if (t == typeof(Byte)) return "TinyInt";
if (t == typeof(UInt16)) return "SmallInt";
if (t == typeof(UInt32)) return "Int";
if (t == typeof(UInt64)) return "BigInt";
if (t == typeof(Single)) return "Real";
if (t == typeof(Double)) return "Float";
if (t == typeof(Decimal)) return "Money";
if (t == typeof(Boolean)) return "Bit";
if (t == typeof(Guid)) return "UniqueIdentifier";
if (t == typeof(Byte[])) return "Image";
if (t == typeof(string)) return "NText";
if (t == typeof(DateTime)) return "DateTime";
if (t == typeof(Char)) return "NChar";
if (t == typeof(Byte[])) return "Binary";

throw new Exception("Unable to get matching SQL CE type for
type " + t.Name);
}

public static SqlDbType GetSQLType (Type t) {

if (t == typeof(SByte)) return SqlDbType.TinyInt;
if (t == typeof(Int16)) return SqlDbType.SmallInt;
if (t == typeof(Int32)) return SqlDbType.Int;
if (t == typeof(Int64)) return SqlDbType.BigInt;
if (t == typeof(Byte)) return SqlDbType.TinyInt;
if (t == typeof(UInt16)) return SqlDbType.SmallInt;
if (t == typeof(UInt32)) return SqlDbType.Int;
if (t == typeof(UInt64)) return SqlDbType.BigInt;
if (t == typeof(Single)) return SqlDbType.Real;
if (t == typeof(Double)) return SqlDbType.Float;
if (t == typeof(Decimal)) return SqlDbType.Money;
if (t == typeof(Boolean)) return SqlDbType.Bit;
if (t == typeof(Guid)) return SqlDbType.UniqueIdentifier;
if (t == typeof(Byte[])) return SqlDbType.Image;
if (t == typeof(string)) return SqlDbType.NText;
if (t == typeof(DateTime)) return SqlDbType.DateTime;
if (t == typeof(Char)) return SqlDbType.NChar;
if (t == typeof(Byte[])) return SqlDbType.Binary;

throw new Exception("Unable to get matching SQL CE type for
type " + t.Name);
}

// Store a dataset to the SQL CE.

public static void storeDataToSQLCE( DataSet data, string dataFile )
{
if (File.Exists(dataFile)) // Get
rid of existing database file
File.Delete(dataFile);

SqlCeEngine en = new SqlCeEngine("Data Source = " + dataFile );
//
Create new database engine
en.CreateDatabase(); //
Create a new database

SqlCeConnection con = new SqlCeConnection("Data Source = " +
dataFile );
//
Create a new connection
con.Open(); // Open
this connection

foreach (DataTable table in data.Tables ) { //
Create tables one by one

SqlCeCommand cmd = con.CreateCommand(); // Prepare Create
table command

StringBuilder command = new StringBuilder(1024); //
Assume we have pretty long command

command.Append("Create Table \""); //
Command string:
command.Append( table.TableName ); //
Create Table "TableName" ("ColumnName" ColumnType, ... )
command.Append( "\" (");

foreach ( DataColumn c in table.Columns) { // Add
all columns

command.Append ("\"");
command.Append (c.ColumnName); // Add
column name
command.Append ("\" ");
command.Append (GetSQLTypeName(c.DataType)); // And
column SQL type

// Add special column features:
//
// Identity(_seed, _increment) Autoincrement Could
not set this as column will be read only
// Primary Key Primary Key
// Default _value Sets default value
// Unique For unique columns
// Not Null Null is not allowed


if ( c.DefaultValue != DBNull.Value ) { //
Default value is set?
command.Append (String.Format(" Default '{0}'",
c.DefaultValue));
}

if ( !c.AllowDBNull ) { //
Could not be null ?
command.Append (" Not Null"); // Mark
it as Not Null
}

if ( c.Unique ) { //
Unique column ?
DataColumn[] pk = table.PrimaryKey; // Get
primry key column(s)

if ( pk != null && pk.Length > 1 ) // Only
one column allowed as a primary key in SQL CE
throw new System.Exception("Only one column
allowed as a primary key in SQL CE");

if ( null != pk && pk.Length == 1 && pk[0] == c) {

//
Primary key ?
command.Append (" Primary Key"); // Mark
it as such
}
else {
command.Append (" Unique"); // Mark
it as unique
}
}

command.Append (','); // Add
separator
}

command.Replace (',', ')', command.Length - 1, 1); //
Replace last comma with ')'

cmd.CommandText = command.ToString(); // Set
command

// Console.WriteLine ("Create command: \n{0}",
cmd.CommandText);

cmd.ExecuteNonQuery(); // Do
it - create a table

cmd.Parameters.Clear(); // Do
some cleanup


// At this point we have a database with an empty table
ready to be populated...

SqlCeDataAdapter da = new SqlCeDataAdapter(); //
Prepare data adapter

command.Remove(0, command.Length); //
Clean up old command

command.Append ("Insert Into \""); //
Insert command
command.Append ( table.TableName );
command.Append ("\" (");

foreach (DataColumn column in table.Columns) { // Add
column names
command.Append ('"');
command.Append ( column.ColumnName );
command.Append ("\","); //
Separated by commas

cmd.Parameters.Add("@" + column.ColumnName, // Add
parameters to q query
GetSQLType (column.DataType),
column.MaxLength > 0 ?
column.MaxLength : 0,
column.ColumnName);
}

command.Remove(command.Length - 1, 1); //
Remove last comma

command.Append(") Values (");

for (int i = table.Columns.Count; i-- > 0; ) // Add
correct number
command.Append( "?,"); // of
queston marks

command.Replace (',', ')', command.Length - 1, 1); //
Replace last comma with ')'

cmd.CommandText = command.ToString(); // Set
insert command

da.InsertCommand = cmd; //
Store our insert command


da.Update(table); //
Update table in the SQL CE

cmd.Parameters.Clear(); // Do
some cleanup

//Verification
Console.WriteLine("VERIFYING");
#region VERIFICATION
cmd = con.CreateCommand(); // Prepare Create table command
string vcommand = String.Format("select COUNT(*) from
{0}",table.TableName);
cmd.CommandText = vcommand; // Set command

int count = (int)cmd.ExecuteScalar(); //
Do it - create a table
if(count != table.Rows.Count)
{
Console.WriteLine("We did not store Expected number of records");
Console.WriteLine("Expected was {0}", table.Rows.Count);
Console.WriteLine("Actual was {0}",count);
throw new Exception("Error in Verification");
}
#endregion
Console.WriteLine("DONE WITH VERIFICATION");

}

con.Close(); //
Close connection.
}

// Restore a dataset from the SQL CE

public static DataSet restoreDataFromSQLCE( string dataFile)
{
DataSet data = new DataSet(); //
Create new dataset

data.EnforceConstraints = false;

SqlCeConnection con = new SqlCeConnection("Data Source = " +
dataFile );
//
Create a new connection
SqlCeDataReader rdr = null;
try
{
con.Open(); //
Open this connection

// Now enumerate all user tables

SqlCeCommand cmd = con.CreateCommand(); //
Prepare command

cmd.CommandText = "Select table_type, table_name From
Information_Schema.Tables";
// Query table type and name
rdr = cmd.ExecuteReader(); // Get data

while(rdr.Read()) //
Now read it
{
if ( rdr.GetString(0) == "TABLE" ) //
Is it a user's table ?
{
string tableName = rdr.GetString(1); //
Get table name

SqlCeDataAdapter da = new SqlCeDataAdapter(); //
Create data adapter to fill our DataSet

cmd.CommandType = CommandType.TableDirect; //
Use direct table access to load data

cmd.CommandText = tableName; //
Set table name

da.SelectCommand = cmd; //
Set command to be used with data adapter

DataTable table = new DataTable (); //
Create DataTable to be filled

da.Fill(table); //
Fill table with data

table.TableName = tableName; //
Rename table

data.Tables.Add(table); //
Add table to the dataset
}
}
data.EnforceConstraints = true;
return data;
}
finally
{
if(null != rdr)
rdr.Close();
// We're done reading
if(null != con)
con.Close();
// Close this connection
}


}

public static void ShowErrors(SqlCeException e)
{
SqlCeErrorCollection errorCollection = e.Errors;

StringBuilder bld = new StringBuilder();
Exception inner = e.InnerException;

foreach (SqlCeError err in errorCollection)
{
bld.Append("\n Error Code: " + err.HResult.ToString("X"));
bld.Append("\n Message : " + err.Message);
bld.Append("\n Minor Err.: " + err.NativeError);
bld.Append("\n Source : " + err.Source);

foreach (int numPar in err.NumericErrorParameters)
{
if (0 != numPar) bld.Append("\n Num. Par. : " + numPar);
}

foreach (string errPar in err.ErrorParameters)
{
if (String.Empty != errPar) bld.Append("\n Err. Par. :
" + errPar);
}

Console.WriteLine(bld.ToString());
bld.Remove(0, bld.Length);
}
}
}
 
Thanks for the code snippet.

Unfortunately this is generating a "System.InvalidOperationException" which
has the helpful message "Update" when trying to process the line
"da.Update(table);"

thoughts??

thanks


Mark Ihimoyan said:
Here is some code you might find helpful.

It contains some helper functions for storing a dataset to SqlCe and also
restoring a dataset from a SqlCe database

class manipulateSQLCE
{
public static string GetSQLTypeName (Type t) {

if (t == typeof(SByte)) return "TinyInt";
if (t == typeof(Int16)) return "SmallInt";
if (t == typeof(Int32)) return "Int";
if (t == typeof(Int64)) return "BigInt";
if (t == typeof(Byte)) return "TinyInt";
if (t == typeof(UInt16)) return "SmallInt";
if (t == typeof(UInt32)) return "Int";
if (t == typeof(UInt64)) return "BigInt";
if (t == typeof(Single)) return "Real";
if (t == typeof(Double)) return "Float";
if (t == typeof(Decimal)) return "Money";
if (t == typeof(Boolean)) return "Bit";
if (t == typeof(Guid)) return "UniqueIdentifier";
if (t == typeof(Byte[])) return "Image";
if (t == typeof(string)) return "NText";
if (t == typeof(DateTime)) return "DateTime";
if (t == typeof(Char)) return "NChar";
if (t == typeof(Byte[])) return "Binary";

throw new Exception("Unable to get matching SQL CE type for
type " + t.Name);
}

public static SqlDbType GetSQLType (Type t) {

if (t == typeof(SByte)) return SqlDbType.TinyInt;
if (t == typeof(Int16)) return SqlDbType.SmallInt;
if (t == typeof(Int32)) return SqlDbType.Int;
if (t == typeof(Int64)) return SqlDbType.BigInt;
if (t == typeof(Byte)) return SqlDbType.TinyInt;
if (t == typeof(UInt16)) return SqlDbType.SmallInt;
if (t == typeof(UInt32)) return SqlDbType.Int;
if (t == typeof(UInt64)) return SqlDbType.BigInt;
if (t == typeof(Single)) return SqlDbType.Real;
if (t == typeof(Double)) return SqlDbType.Float;
if (t == typeof(Decimal)) return SqlDbType.Money;
if (t == typeof(Boolean)) return SqlDbType.Bit;
if (t == typeof(Guid)) return SqlDbType.UniqueIdentifier;
if (t == typeof(Byte[])) return SqlDbType.Image;
if (t == typeof(string)) return SqlDbType.NText;
if (t == typeof(DateTime)) return SqlDbType.DateTime;
if (t == typeof(Char)) return SqlDbType.NChar;
if (t == typeof(Byte[])) return SqlDbType.Binary;

throw new Exception("Unable to get matching SQL CE type for
type " + t.Name);
}

// Store a dataset to the SQL CE.

public static void storeDataToSQLCE( DataSet data, string dataFile )
{
if (File.Exists(dataFile)) // Get
rid of existing database file
File.Delete(dataFile);

SqlCeEngine en = new SqlCeEngine("Data Source = " + dataFile );
//
Create new database engine
en.CreateDatabase(); //
Create a new database

SqlCeConnection con = new SqlCeConnection("Data Source = " +
dataFile );
//
Create a new connection
con.Open(); // Open
this connection

foreach (DataTable table in data.Tables ) { //
Create tables one by one

SqlCeCommand cmd = con.CreateCommand(); // Prepare Create
table command

StringBuilder command = new StringBuilder(1024); //
Assume we have pretty long command

command.Append("Create Table \""); //
Command string:
command.Append( table.TableName ); //
Create Table "TableName" ("ColumnName" ColumnType, ... )
command.Append( "\" (");

foreach ( DataColumn c in table.Columns) { // Add
all columns

command.Append ("\"");
command.Append (c.ColumnName); // Add
column name
command.Append ("\" ");
command.Append (GetSQLTypeName(c.DataType)); // And
column SQL type

// Add special column features:
//
// Identity(_seed, _increment) Autoincrement Could
not set this as column will be read only
// Primary Key Primary Key
// Default _value Sets default value
// Unique For unique columns
// Not Null Null is not allowed


if ( c.DefaultValue != DBNull.Value ) { //
Default value is set?
command.Append (String.Format(" Default '{0}'",
c.DefaultValue));
}

if ( !c.AllowDBNull ) { //
Could not be null ?
command.Append (" Not Null"); // Mark
it as Not Null
}

if ( c.Unique ) { //
Unique column ?
DataColumn[] pk = table.PrimaryKey; // Get
primry key column(s)

if ( pk != null && pk.Length > 1 ) // Only
one column allowed as a primary key in SQL CE
throw new System.Exception("Only one column
allowed as a primary key in SQL CE");

if ( null != pk && pk.Length == 1 && pk[0] == c) {

//
Primary key ?
command.Append (" Primary Key"); // Mark
it as such
}
else {
command.Append (" Unique"); // Mark
it as unique
}
}

command.Append (','); // Add
separator
}

command.Replace (',', ')', command.Length - 1, 1); //
Replace last comma with ')'

cmd.CommandText = command.ToString(); // Set
command

// Console.WriteLine ("Create command: \n{0}",
cmd.CommandText);

cmd.ExecuteNonQuery(); // Do
it - create a table

cmd.Parameters.Clear(); // Do
some cleanup


// At this point we have a database with an empty table
ready to be populated...

SqlCeDataAdapter da = new SqlCeDataAdapter(); //
Prepare data adapter

command.Remove(0, command.Length); //
Clean up old command

command.Append ("Insert Into \""); //
Insert command
command.Append ( table.TableName );
command.Append ("\" (");

foreach (DataColumn column in table.Columns) { // Add
column names
command.Append ('"');
command.Append ( column.ColumnName );
command.Append ("\","); //
Separated by commas

cmd.Parameters.Add("@" + column.ColumnName, // Add
parameters to q query
GetSQLType (column.DataType),
column.MaxLength > 0 ?
column.MaxLength : 0,
column.ColumnName);
}

command.Remove(command.Length - 1, 1); //
Remove last comma

command.Append(") Values (");

for (int i = table.Columns.Count; i-- > 0; ) // Add
correct number
command.Append( "?,"); // of
queston marks

command.Replace (',', ')', command.Length - 1, 1); //
Replace last comma with ')'

cmd.CommandText = command.ToString(); // Set
insert command

da.InsertCommand = cmd; //
Store our insert command


da.Update(table); //
Update table in the SQL CE

cmd.Parameters.Clear(); // Do
some cleanup

//Verification
Console.WriteLine("VERIFYING");
#region VERIFICATION
cmd = con.CreateCommand(); // Prepare Create table command
string vcommand = String.Format("select COUNT(*) from
{0}",table.TableName);
cmd.CommandText = vcommand; // Set command

int count = (int)cmd.ExecuteScalar(); //
Do it - create a table
if(count != table.Rows.Count)
{
Console.WriteLine("We did not store Expected number of records");
Console.WriteLine("Expected was {0}", table.Rows.Count);
Console.WriteLine("Actual was {0}",count);
throw new Exception("Error in Verification");
}
#endregion
Console.WriteLine("DONE WITH VERIFICATION");

}

con.Close(); //
Close connection.
}

// Restore a dataset from the SQL CE

public static DataSet restoreDataFromSQLCE( string dataFile)
{
DataSet data = new DataSet(); //
Create new dataset

data.EnforceConstraints = false;

SqlCeConnection con = new SqlCeConnection("Data Source = " +
dataFile );
//
Create a new connection
SqlCeDataReader rdr = null;
try
{
con.Open(); //
Open this connection

// Now enumerate all user tables

SqlCeCommand cmd = con.CreateCommand(); //
Prepare command

cmd.CommandText = "Select table_type, table_name From
Information_Schema.Tables";
// Query table type and name
rdr = cmd.ExecuteReader(); // Get data

while(rdr.Read()) //
Now read it
{
if ( rdr.GetString(0) == "TABLE" ) //
Is it a user's table ?
{
string tableName = rdr.GetString(1); //
Get table name

SqlCeDataAdapter da = new SqlCeDataAdapter(); //
Create data adapter to fill our DataSet

cmd.CommandType = CommandType.TableDirect; //
Use direct table access to load data

cmd.CommandText = tableName; //
Set table name

da.SelectCommand = cmd; //
Set command to be used with data adapter

DataTable table = new DataTable (); //
Create DataTable to be filled

da.Fill(table); //
Fill table with data

table.TableName = tableName; //
Rename table

data.Tables.Add(table); //
Add table to the dataset
}
}
data.EnforceConstraints = true;
return data;
}
finally
{
if(null != rdr)
rdr.Close();
// We're done reading
if(null != con)
con.Close();
// Close this connection
}


}

public static void ShowErrors(SqlCeException e)
{
SqlCeErrorCollection errorCollection = e.Errors;

StringBuilder bld = new StringBuilder();
Exception inner = e.InnerException;

foreach (SqlCeError err in errorCollection)
{
bld.Append("\n Error Code: " + err.HResult.ToString("X"));
bld.Append("\n Message : " + err.Message);
bld.Append("\n Minor Err.: " + err.NativeError);
bld.Append("\n Source : " + err.Source);

foreach (int numPar in err.NumericErrorParameters)
{
if (0 != numPar) bld.Append("\n Num. Par. : " + numPar);
}

foreach (string errPar in err.ErrorParameters)
{
if (String.Empty != errPar) bld.Append("\n Err. Par. :
" + errPar);
}

Console.WriteLine(bld.ToString());
bld.Remove(0, bld.Length);
}
}
}
Click to expand...
 
I suggest you print out the insert command between the following 2 lines of
code to aid in troubleshooting this.
That way I could tell what caused the exception. It will also be helpful to
tell me about the dataset.

cmd.CommandText = command.ToString(); // Set
insert command
Console.WriteLine(cmd.CommandText);
da.InsertCommand = cmd; // Store
our insert command
Thanks.
 
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