/// <summary>
/// Creates and runs an ALTER TABLE SQL statement to drop the given column from the table
/// </summary>
/// <param name="column">The column to drop</param>
public void DropColumn(DiscoveredColumn column)
{
using (IManagedConnection connection = Database.Server.GetManagedConnection())
{
Helper.DropColumn(connection.Connection, column);
}
}
/// <summary>
/// API constructor, instead use <see cref="DiscoveredTable.DiscoverColumns"/> instead.
/// </summary>
/// <param name="r">All the values in r will be copied into the Dictionary property of this class called ProprietaryDatatype</param>
/// <param name="sqlType">Your infered SQL data type for it e.g. varchar(50)</param>
/// <param name="column">The column it belongs to, can be null e.g. if your datatype belongs to a DiscoveredParameter instead</param>
public DiscoveredDataType(DbDataReader r, string sqlType, DiscoveredColumn column)
{
SQLType = sqlType;
Column = column;
for (int i = 0; i < r.FieldCount; i++)
{
ProprietaryDatatype.Add(r.GetName(i), r.GetValue(i));
}
}
public DbParameter GetParameter(DbParameter p, DiscoveredColumn discoveredColumn, object value, CultureInfo culture)
{
try
{
if (culture == null)
{
culture = CultureInfo.CurrentCulture;
}
if (!factories.ContainsKey(culture))
{
factories.Add(culture, new TypeDeciderFactory(culture));
}
var tt = TypeTranslater;
p.DbType = tt.GetDbTypeForSQLDBType(discoveredColumn.DataType.SQLType);
var cSharpType = tt.GetCSharpTypeForSQLDBType(discoveredColumn.DataType.SQLType);
if (IsBasicallyNull(value))
{
p.Value = DBNull.Value;
}
else
if (value is string strVal && factories[culture].IsSupported(cSharpType)) //if the input is a string and it's for a hard type e.g. TimeSpan
{
var decider = factories[culture].Create(cSharpType);
var o = decider.Parse(strVal);
//Not all DBMS support DBParameter.Value = new TimeSpan(...);
if (o is TimeSpan)
{
o = FormatTimespanForDbParameter((TimeSpan)o);
}
p.Value = o;
}
else
{
p.Value = value;
}
}
public DiscoveredRelationship AddForeignKey(DiscoveredColumn foreignKey, DiscoveredColumn primaryKey, bool cascadeDeletes, string constraintName = null, DatabaseOperationArgs args = null)
{
return(AddForeignKey(new Dictionary <DiscoveredColumn, DiscoveredColumn> {
{ foreignKey, primaryKey }
}, cascadeDeletes, constraintName, args));
}
public abstract void DropColumn(DbConnection connection, DiscoveredColumn columnToDrop);
/// <summary>
/// Based on column name and Table
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
protected bool Equals(DiscoveredColumn other)
{
return(string.Equals(_name, other._name) && Equals(Table, other.Table));
}
