/// <summary>
/// Updates an existing database table to 'match' a schema by adding any missing columns.
/// </summary>
/// <param name="adapter">Open adapter to a database.</param>
/// <param name="schema">The schema to use to update the database.</param>
/// <returns>True if table is successfully updated to match schema.</returns>
public static bool UpdateTableToMatchSchema(IDbAdapter adapter, DataTable schema)
{
// Check if we need to update the db schema and/or this result schema.
var dbTable = adapter.GetSchema(schema.TableName);
if (!schema.SchemaEquals(dbTable))
{
try
{
// Insert any missing columns into the database.
adapter.AddColumnsToTableToMatchSchema(dbTable.TableName, schema);
return true;
}
catch (DbException ex)
{
Log.Error("Failed to initialize database writer: " + ex.Message);
return false;
}
}
Log.Debug("Database table already matches schema; nothing to update.");
return true;
}
/// <summary>
/// Updates an existing database table to 'match' a schema by adding any missing columns.
/// </summary>
/// <param name="adapter">Open adapter to a database.</param>
/// <param name="schema">The schema to use to update the database.</param>
/// <returns>True if table is successfully updated to match schema.</returns>
public static bool UpdateTableToMatchSchema(IDbAdapter adapter, DataTable schema)
{
// Check if we need to update the db schema and/or this result schema.
var dbTable = adapter.GetSchema(schema.TableName);
if (!schema.SchemaEquals(dbTable))
{
try
{
// Insert any missing columns into the database.
adapter.AddColumnsToTableToMatchSchema(dbTable.TableName, schema);
return(true);
}
catch (DbException ex)
{
Log.Error("Failed to initialize database writer: " + ex.Message);
return(false);
}
}
Log.Debug("Database table already matches schema; nothing to update.");
return(true);
}
/// <summary>
/// Updates a schema to 'match' an existing database table by copying it.
/// </summary>
/// <param name="adapter">Open adapter to a database.</param>
/// <param name="schema">The schema to update.</param>
/// <returns></returns>
public static bool UpdateSchemaToMatchTable(IDbAdapter adapter, DataTable schema)
{
// Copy the DB table's schema back over the top of our in-memory schema to ensure parity.
try
{
// Check to see if overwriting the schema will yield inconsistencies.
var existingTableSchema = adapter.GetSchema(schema.TableName);
foreach (DataColumn column in schema.Columns)
{
if (!existingTableSchema.Columns.Contains(column.ColumnName))
{
Log.Error(String.Format("Cannot update local schema to match database table; column '{0}' exists in the schema, but not the database table.", column.ColumnName));
return(false);
}
if (existingTableSchema.Columns[column.ColumnName].DataType != column.DataType)
{
Log.Error(String.Format("Cannot update local schema to match database table; data types are inconsistent. [Schema='{0}', DbTable='{1}']", column.DataType, existingTableSchema.Columns[column.ColumnName].DataType));
return(false);
}
if (existingTableSchema.Columns[column.ColumnName].AllowDBNull != column.AllowDBNull)
{
Log.Error(String.Format("Cannot update local schema to match database table; inconsistencies in 'AllowDBNull' parameter. [Schema='{0}', DbTable='{1}']", column.AllowDBNull, existingTableSchema.Columns[column.ColumnName].AllowDBNull));
return(false);
}
}
// Copy the remote database's schema over the top of our in-memory schema.
schema = existingTableSchema.Copy();
Log.Debug(String.Format("Updated internal schema to match database table '{0}'.", schema.TableName));
return(true);
}
catch (DbException ex)
{
Log.Error(String.Format("Error updating schema '{0}' from database: {1}", schema.TableName, ex.Message));
return(false);
}
}
/// <summary>
/// Updates a schema to 'match' an existing database table by copying it.
/// </summary>
/// <param name="adapter">Open adapter to a database.</param>
/// <param name="schema">The schema to update.</param>
/// <returns></returns>
public static bool UpdateSchemaToMatchTable(IDbAdapter adapter, DataTable schema)
{
// Copy the DB table's schema back over the top of our in-memory schema to ensure parity.
try
{
// Check to see if overwriting the schema will yield inconsistencies.
var existingTableSchema = adapter.GetSchema(schema.TableName);
foreach (DataColumn column in schema.Columns)
{
if (!existingTableSchema.Columns.Contains(column.ColumnName))
{
Log.Error(String.Format("Cannot update local schema to match database table; column '{0}' exists in the schema, but not the database table.", column.ColumnName));
return false;
}
if (existingTableSchema.Columns[column.ColumnName].DataType != column.DataType)
{
Log.Error(String.Format("Cannot update local schema to match database table; data types are inconsistent. [Schema='{0}', DbTable='{1}']", column.DataType, existingTableSchema.Columns[column.ColumnName].DataType));
return false;
}
if (existingTableSchema.Columns[column.ColumnName].AllowDBNull != column.AllowDBNull)
{
Log.Error(String.Format("Cannot update local schema to match database table; inconsistencies in 'AllowDBNull' parameter. [Schema='{0}', DbTable='{1}']", column.AllowDBNull, existingTableSchema.Columns[column.ColumnName].AllowDBNull));
return false;
}
}
// Copy the remote database's schema over the top of our in-memory schema.
schema = existingTableSchema.Copy();
Log.Debug(String.Format("Updated internal schema to match database table '{0}'.", schema.TableName));
return true;
}
catch (DbException ex)
{
Log.Error(String.Format("Error updating schema '{0}' from database: {1}", schema.TableName, ex.Message));
return false;
}
}
