public override string SerializeAlterTableFieldsModifier(SQLTableFields.AlterModeType alterMode)
{
if (alterMode == SQLTableFields.AlterModeType.Drop)
throw new NotSupportedException("SQLite does not support dropping a column");
else
return base.SerializeAlterTableFieldsModifier(alterMode);
}
public override string SerializeColumnAlterMode(SQLTableFields.AlterModeType alterMode)
{
switch (alterMode)
{
case SQLTableFields.AlterModeType.Modify:
return "MODIFY COLUMN";
default:
return base.SerializeColumnAlterMode(alterMode);
}
}
public virtual string SerializeColumnAlterMode(SQLTableFields.AlterModeType alterMode)
{
switch (alterMode)
{
case SQLTableFields.AlterModeType.Add:
return "ADD";
case SQLTableFields.AlterModeType.Modify:
return "ALTER COLUMN";
case SQLTableFields.AlterModeType.Drop:
return "DROP COLUMN";
default:
throw new NotImplementedException();
}
}
/// <summary>
/// The field modifier that is used before all of the fields modifications are listed.
/// Typically used by SQL Server to indicate the type of operation to be performed on ALL fields.
/// </summary>
/// <param name="tableFields"></param>
/// <returns></returns>
public virtual string SerializeAlterTableFieldsModifier(SQLTableFields.AlterModeType alterMode)
{
return SerializeColumnAlterMode(alterMode);
}
/// <summary>
/// </summary>
/// <param name="includeColumnModifier">
/// Indicates whether the ADD, MODIFY or DROP modifiers are required for each column.
/// When utilised from SQLCreateTable this will always be false. However, for SQLAlterTable this will be true.</param>
/// <returns></returns>
public virtual string SerializeTableFields(SQLTableFields tableFields, bool includeColumnModifier)
{
var tokens = new TokenSerializer();
//Include mode when altering a table, otherwise when creating a table the mode is not required.
if (includeColumnModifier)
tokens.Add(SerializeAlterTableFieldsModifier(tableFields.AlterMode));
var fieldsTokens = new TokenSerializer(", ");
foreach (SQLTableFieldBase field in tableFields)
{
var fieldToken = new TokenSerializer();
if (includeColumnModifier)
fieldToken.Add(SerializeAlterTableFieldModifier(tableFields.AlterMode));
fieldToken.Add(field.SQL(this, tableFields.AlterMode));
fieldsTokens.Add(fieldToken.ToString());
}
tokens.Add(fieldsTokens.ToString());
return tokens.ToString();
}
/// <summary>
/// The field modifier that is used before each field that is being modified.
/// Typically used by MySQL the type of operation to be performed on each field.
/// </summary>
/// <param name="tableFields"></param>
/// <returns></returns>
public virtual string SerializeAlterTableFieldModifier(SQLTableFields.AlterModeType alterMode)
{
return String.Empty;
}
public virtual string SerializeTableFieldComputed(SQLTableFieldComputed tableFieldComputed, SQLTableFields.AlterModeType alterMode)
{
if (alterMode == SQLTableFields.AlterModeType.Drop)
throw new InvalidOperationException("Computed columns cannot be used for dropping fields");
return tableFieldComputed.NameAsExpression.SQL(this) + " AS (" + tableFieldComputed.Computation.SQL(this) + ")";
}
public virtual string SerializeTableField(SQLTableField field, SQLTableFields.AlterModeType alterMode)
{
var tokens = new TokenSerializer();
if (alterMode == SQLTableFields.AlterModeType.Drop)
tokens.Add(SerializeTableFieldAsName(field));
else
{
tokens.Add(SerializeTableFieldAsName(field));
tokens.Add(SerializeTableFieldDataType(field));
tokens.Add(SerializeTableFieldCollationOption(field));
tokens.Add(SerializeTableFieldDefaultOption(field));
tokens.Add(SerializeTableFieldNullableOption(field));
tokens.Add(SerializeTableFieldKeyTypeOption(field));
}
return tokens.ToString();
}
public SQLCreateTable()
{
pobjFields = new SQLTableFields();
pobjFields.AlterMode = SQLTableFields.AlterModeType.Add; //set that fields can only be added
}
public override string SerializeAlterTableFieldsModifier(SQLTableFields.AlterModeType alterMode)
{
// For MySQL the modifiers are added for each column not for all of the columns.
// So override the SerializeAlterTableFieldModifier instead.
return String.Empty;
}
public override string SerializeAlterTableFieldModifier(SQLTableFields.AlterModeType alterMode)
{
// For MySQL the modifiers are added for each column not for all of the columns.
return SerializeColumnAlterMode(alterMode);
}
public override string SerializeTableField(SQLTableField field, SQLTableFields.AlterModeType alterMode)
{
// if altering or creating a field append the AUTOINCREMENT. Field format: name datatype default nullable keytype AUTOINCREMENT
if (alterMode != SQLTableFields.AlterModeType.Drop && field.AutoIncrements)
return base.SerializeTableField(field, alterMode) + " AUTOINCREMENT";
else
return base.SerializeTableField(field, alterMode);
}
