/// <summary>
/// Returns a string representation of the column for use in CREATE TABLE statements
/// </summary>
public string ToExpression(SqlFlavor flavor = SqlFlavor.MSSQL)
{
switch (flavor)
{
case SqlFlavor.MSSQL:
return(string.Format("[{0}] {1} {2}", name, dataType.ToString(), isNullable ? "NULL" : "NOT NULL"));
case SqlFlavor.MySQL:
return(string.Format("{0} {1} {2}", name, dataType.ToString(), isNullable ? "NULL" : "NOT NULL"));
default:
throw new NotImplementedException("No defined ToExpression for sql flavor: " + flavor.ToString());
}
}
/// <summary>
/// Map source column type to Vertica column type, to the form of: data_type_name[(octet_length)]
/// NOTE: other DataUtils may consider implementing this method to map data types correctly
/// </summary>
/// <param name="sourceFlavor">SQL type of the data source</param>
/// <param name="sourceDataType">Data type in the source</param>
/// <param name="modifier">Modifier configured for the column</param>
/// <returns>string representing Vertica column type in the form of: data_type_name[(octet_length)]</returns>
public string MapColumnTypeName(SqlFlavor sourceFlavor, DataType sourceDataType, ColumnModifier modifier)
{
string typeName = "";
string modDataType = DataType.MapDataType(sourceFlavor, SqlFlavor.Vertica, sourceDataType.BaseType);
switch (sourceFlavor)
{
case SqlFlavor.MSSQL:
// these MSSQL types will carry over the length specs (CHARACTER_MAXIMUM_LENGTH) from MSSQL to Vertica
// NOTE: for these types, we have to make sure, in the data mapping file, the mapped-to Vertica data type is
// specified without the (LENGTH) suffix. That is:
// correct: char => char
// wrong: char => char(65000)
var typesUsingLength = new string[6] {
"binary", "char", "nchar", "nvarchar", "varbinary", "varchar"
};
// these MSSQL types will carry over the scale and precision specs (NUMERIC_PRECISION, NUMERIC_SCALE) from MSSQL to Vertica
var typesUsingScale = new string[4] {
"decimal", "money", "numeric", "smallmoney"
};
if (modifier != null)
{
// if modifier is specified, and matches regex, apply modifier to get type name
if (Regex.IsMatch(modDataType, @".*\(\d+\)$"))
{
// if (LENGTH) is specified in the mapped data type
typeName = Regex.Replace(modDataType, @"\d+", modifier.length.ToString());
}
else
{
// there is no (LENGTH) in the mapped data type
typeName = modDataType + "(" + modifier.length.ToString() + ")";
}
}
else
{
// if no modifier is specified, or regex does not match
string suffix = "";
if (typesUsingLength.Contains(sourceDataType.BaseType) && sourceDataType.CharacterMaximumLength != null)
{
// if this type uses length, and its CHARACTER_MAXIMUM_LENGTH is set in MSSQL
// if CHARACTER_MAXIMUM_LENGTH is -1 (max) [(n)varchar(max) types stored with a maxlen of -1 in MSSQL]
// or if CHARACTER_MAXIMUM_LENGTH is greater than Vertica string length,
// then change that to Vertica string length
// otherwise keep the CHARACTER_MAXIMUM_LENGTH value from MSSQL
suffix = "(" + ((sourceDataType.CharacterMaximumLength == -1 || sourceDataType.CharacterMaximumLength > Config.VerticaStringLength)
? Convert.ToString(Config.VerticaStringLength) : Convert.ToString(sourceDataType.CharacterMaximumLength)) + ")";
}
else if (typesUsingScale.Contains(sourceDataType.BaseType) && sourceDataType.NumericPrecision != null && sourceDataType.NumericScale != null)
{
// if this type uses scale and precision
// and both information are available from MSSQL
suffix = "(" + sourceDataType.NumericPrecision + ", " + sourceDataType.NumericScale + ")";
}
typeName = modDataType + suffix;
}
break;
default:
throw new NotImplementedException("Vertica column type name mapping is not implementation for this source: " + sourceFlavor.ToString());
}
return(typeName);
}
