public virtual void Process(AlterColumnExpression expression)
{
Process(Generator.Generate(expression));
}
public abstract string Generate(AlterColumnExpression expression);
public override string Generate(AlterColumnExpression expression)
{
return(string.Format("ALTER TABLE {0}.{1}", Quoter.QuoteSchemaName(expression.SchemaName), base.Generate(expression)));
}
public override string Generate(AlterColumnExpression expression)
{
truncator.Truncate(expression);
return(compatabilityMode.HandleCompatabilty("Alter column is not supported as expected"));
}
public override void Process(AlterColumnExpression expression)
{
base.Process(expression.ToLower());
}
public string GenerateDescriptionStatement(AlterColumnExpression expression)
{
return(string.Empty);
}
public override void Process(AlterColumnExpression expression)
{
Truncator.Truncate(expression);
CheckColumn(expression.TableName, expression.Column.Name);
FirebirdSchemaProvider schema = new FirebirdSchemaProvider(this, _quoter);
FirebirdTableSchema table = schema.GetTableSchema(expression.TableName);
ColumnDefinition colDef = table.Definition.Columns.FirstOrDefault(x => x.Name == _quoter.ToFbObjectName(expression.Column.Name));
var generator = (FirebirdGenerator)Generator;
var tableName = expression.Column.TableName ?? expression.TableName;
//Change nullable constraint
if (colDef == null || colDef.IsNullable != expression.Column.IsNullable)
{
string nullConstraintCommand;
if (IsFirebird3)
{
nullConstraintCommand = generator.GenerateSetNull3(tableName, expression.Column);
}
else
{
nullConstraintCommand = generator.GenerateSetNullPre3(tableName, expression.Column);
}
InternalProcess(nullConstraintCommand);
}
//Change default value
if (colDef == null || !FirebirdGenerator.DefaultValuesMatch(colDef, expression.Column))
{
IMigrationExpression defaultConstraint;
if (expression.Column.DefaultValue is ColumnDefinition.UndefinedDefaultValue)
{
defaultConstraint = new DeleteDefaultConstraintExpression()
{
SchemaName = expression.SchemaName,
TableName = expression.TableName,
ColumnName = expression.Column.Name
};
}
else
{
defaultConstraint = new AlterDefaultConstraintExpression()
{
ColumnName = expression.Column.Name,
DefaultValue = expression.Column.DefaultValue,
TableName = expression.TableName,
SchemaName = expression.SchemaName
};
}
if (defaultConstraint is DeleteDefaultConstraintExpression deleteDefaultConstraintExpression)
{
InternalProcess(Generator.Generate(deleteDefaultConstraintExpression));
}
else
{
InternalProcess(Generator.Generate((AlterDefaultConstraintExpression)defaultConstraint));
}
}
//Change type
if (colDef == null || !FirebirdGenerator.ColumnTypesMatch(colDef, expression.Column))
{
InternalProcess(generator.GenerateSetType(tableName, expression.Column));
}
bool identitySequenceExists;
try
{
identitySequenceExists = SequenceExists(string.Empty, GetSequenceName(expression.TableName, expression.Column.Name));
}
catch (ArgumentException)
{
identitySequenceExists = false;
}
//Adjust identity generators
if (expression.Column.IsIdentity)
{
if (!identitySequenceExists)
{
CreateSequenceForIdentity(expression.TableName, expression.Column.Name);
}
}
else
{
if (identitySequenceExists)
{
DeleteSequenceForIdentity(expression.TableName, expression.Column.Name);
}
}
}
public override string Generate(AlterColumnExpression expression)
{
return(String.Format("ALTER TABLE {0}.{1} {2}", Quoter.QuoteSchemaName(expression.SchemaName), Quoter.QuoteTableName(expression.TableName), ((PostgresColumn)Column).GenerateAlterClauses(expression.Column)));
}
public override string Generate(AlterColumnExpression expression)
{
throw new NotImplementedException();
}
public override string Generate(AlterColumnExpression expression)
{
return(compatabilityMode.HandleCompatabilty("Sqlite does not support alter column"));
}
