private static long GetLength(ReliableSqlConnection connection, string schemaName, string tableName, string dataColumn, string keyColumn, SqlDbType keyType, object keyValue)
{
using (IDbCommand getLengthCommand = SqlCommandFactory.CreateSqlStreamGetSizeCommand(connection, schemaName, tableName, dataColumn, keyColumn, keyType, keyValue))
{
return(GetLength(connection, getLengthCommand));
}
}
/// <summary>
/// Initializes a new instance of a <see cref="SqlStream"/> object using the specified custom commands for manipulating with the source field holding the underlying data.
/// </summary>
/// <param name="connection">The database connection providing access to the underlying data.</param>
/// <param name="readCommand">The instance of a SQL command responsible for retrieving the data from the source field.</param>
/// <param name="writeCommand">The instance of a SQL command responsible for updating the data held in the source field.</param>
/// <param name="getLengthCommand">The instance of a SQL command responsible for returning the size of the data held in the source field.</param>
public SqlStream(ReliableSqlConnection connection, SqlCommand readCommand, SqlCommand writeCommand, SqlCommand getLengthCommand)
{
Guard.ArgumentNotNull(connection, "connection");
Guard.ArgumentNotNull(readCommand, "readCommand");
Guard.ArgumentNotNull(writeCommand, "writeCommand");
Guard.ArgumentNotNull(getLengthCommand, "getLengthCommand");
this.readCommand = readCommand;
this.writeCommand = writeCommand;
this.commandRetryPolicy = connection.CommandRetryPolicy;
this.dataLength = GetLength(connection, getLengthCommand);
this.disposeCommands = false;
}
/// <summary>
/// Initializes a new instance of a <see cref="SqlStream"/> object using the specified details describing the source field holding the underlying data.
/// </summary>
/// <param name="connection">The database connection providing access to the underlying data.</param>
/// <param name="schemaName">The name of the database schema holding the source table.</param>
/// <param name="tableName">The name of the database table holding the source field containing the data.</param>
/// <param name="dataColumn">The name of the database column holding the data.</param>
/// <param name="keyColumn">The name of the database field which represents a lookup key for the source row containing the data.</param>
/// <param name="keyType">The type of the lookup key.</param>
/// <param name="keyValue">The value of the lookup key.</param>
public SqlStream(ReliableSqlConnection connection, string schemaName, string tableName, string dataColumn, string keyColumn, SqlDbType keyType, object keyValue)
{
Guard.ArgumentNotNull(connection, "connection");
Guard.ArgumentNotNullOrEmptyString(schemaName, "schemaName");
Guard.ArgumentNotNullOrEmptyString(tableName, "tableName");
Guard.ArgumentNotNullOrEmptyString(dataColumn, "dataColumn");
Guard.ArgumentNotNullOrEmptyString(keyColumn, "keyColumn");
Guard.ArgumentNotNull(keyValue, "keyValue");
this.dataLength = GetLength(connection, schemaName, tableName, dataColumn, keyColumn, keyType, keyValue);
this.readCommand = SqlCommandFactory.CreateSqlStreamReadCommand(connection, schemaName, tableName, dataColumn, keyColumn, keyType, keyValue) as SqlCommand;
this.writeCommand = SqlCommandFactory.CreateSqlStreamWriteCommand(connection, schemaName, tableName, dataColumn, keyColumn, keyType, keyValue) as SqlCommand;
this.commandRetryPolicy = connection.CommandRetryPolicy;
this.disposeCommands = true;
}
private static long GetLength(ReliableSqlConnection connection, IDbCommand getLengthCommand)
{
long?length = connection.ExecuteCommand <long?>(getLengthCommand);
return(length.HasValue ? length.Value : 0);
}