NpgsqlDbColumn LoadColumnDefinition(NpgsqlDataReader reader, DatabaseInfo databaseInfo)
{
// Note: we don't set ColumnName and BaseColumnName. These should always contain the
// column alias rather than the table column name (i.e. in case of "SELECT foo AS foo_alias").
// It will be set later.
var column = new NpgsqlDbColumn
{
AllowDBNull = !reader.GetBoolean(reader.GetOrdinal("attnotnull")),
BaseCatalogName = _connection.Database,
BaseSchemaName = reader.GetString(reader.GetOrdinal("nspname")),
BaseServerName = _connection.Host,
BaseTableName = reader.GetString(reader.GetOrdinal("relname")),
ColumnOrdinal = reader.GetInt32(reader.GetOrdinal("attnum")) - 1,
ColumnAttributeNumber = (short)(reader.GetInt16(reader.GetOrdinal("attnum")) - 1),
IsKey = reader.GetBoolean(reader.GetOrdinal("isprimarykey")),
IsReadOnly = !reader.GetBoolean(reader.GetOrdinal("is_updatable")),
IsUnique = reader.GetBoolean(reader.GetOrdinal("isunique")),
DataTypeName = reader.GetString(reader.GetOrdinal("typname")),
TableOID = reader.GetFieldValue<uint>(reader.GetOrdinal("attrelid")),
TypeOID = reader.GetFieldValue<uint>(reader.GetOrdinal("typoid"))
};
column.PostgresType = databaseInfo.ByOID[column.TypeOID];
var defaultValueOrdinal = reader.GetOrdinal("default");
column.DefaultValue = reader.IsDBNull(defaultValueOrdinal) ? null : reader.GetString(defaultValueOrdinal);
column.IsAutoIncrement = column.DefaultValue != null && column.DefaultValue.StartsWith("nextval(");
ColumnPostConfig(column, reader.GetInt32(reader.GetOrdinal("typmod")));
return column;
}
/// <summary>
/// Performs some post-setup configuration that's common to both table columns and non-columns.
/// </summary>
void ColumnPostConfig(NpgsqlDbColumn column, int typeModifier)
{
var typeMapper = _connection.Connector.TypeMapper;
if (typeMapper.Mappings.TryGetValue(column.DataTypeName, out var mapping))
column.NpgsqlDbType = mapping.NpgsqlDbType;
else if (
column.DataTypeName.Contains(".") &&
typeMapper.Mappings.TryGetValue(column.DataTypeName.Split('.')[1], out mapping)
) {
column.NpgsqlDbType = mapping.NpgsqlDbType;
}
column.DataType = typeMapper.TryGetByOID(column.TypeOID, out var handler)
? handler.GetFieldType()
: null;
if (column.DataType != null)
{
column.IsLong = handler is ByteaHandler;
if (handler is IMappedCompositeHandler)
column.UdtAssemblyQualifiedName = column.DataType.AssemblyQualifiedName;
}
if (typeModifier == -1)
return;
// If the column's type is a domain, use its base data type to interpret the typmod
var dataTypeName = column.PostgresType is PostgresDomainType
? ((PostgresDomainType)column.PostgresType).BaseType.Name
: column.DataTypeName;
switch (dataTypeName)
{
case "bpchar":
case "char":
case "varchar":
column.ColumnSize = typeModifier - 4;
break;
case "numeric":
case "decimal":
// See http://stackoverflow.com/questions/3350148/where-are-numeric-precision-and-scale-for-a-field-found-in-the-pg-catalog-tables
column.NumericPrecision = ((typeModifier - 4) >> 16) & 65535;
column.NumericScale = (typeModifier - 4) & 65535;
break;
}
}
NpgsqlDbColumn SetUpNonColumnField(FieldDescription field)
{
// ColumnName and BaseColumnName will be set later
var column = new NpgsqlDbColumn
{
BaseCatalogName = _connection.Database,
BaseServerName = _connection.Host,
IsReadOnly = true,
DataTypeName = field.PostgresType.DisplayName,
TypeOID = field.TypeOID,
TableOID = field.TableOID,
ColumnAttributeNumber = field.ColumnAttributeNumber,
PostgresType = field.PostgresType
};
ColumnPostConfig(column, field.TypeModifier);
return column;
}