public virtual string GenerateDescriptionStatement(Expressions.AlterColumnExpression expression)
{
if (string.IsNullOrEmpty(expression.Column.ColumnDescription))
{
return(string.Empty);
}
string initialDescriptionStatement = GenerateColumnDescription(string.Empty, expression.SchemaName, expression.TableName, expression.Column.Name, "Description:" + expression.Column.ColumnDescription);
if (expression.Column.AdditionalColumnDescriptions.Count == 0)
{
return(initialDescriptionStatement);
}
else
{
initialDescriptionStatement = "Description:" + expression.Column.ColumnDescription;
var descriptionsList = new List <string>
{
initialDescriptionStatement
};
descriptionsList.AddRange(from description in expression.Column.AdditionalColumnDescriptions
let newDescriptionStatement = description.Key + ":" + description.Value
select newDescriptionStatement);
return(GenerateColumnDescription("Description", expression.SchemaName, expression.TableName, expression.Column.Name, string.Join("\r\n", descriptionsList)));
}
}
public virtual string GenerateDescriptionStatement(Expressions.AlterColumnExpression expression)
{
if (string.IsNullOrEmpty(expression.Column.ColumnDescription))
{
return(string.Empty);
}
return(GenerateColumnDescription(expression.SchemaName, expression.TableName, expression.Column.Name, expression.Column.ColumnDescription));
}
public override string Generate(Expressions.AlterColumnExpression expression)
{
try
{
// throws an exception of an attempt is made to alter an identity column, as it is not supported by most version of DB2.
return(string.Format("ALTER TABLE {0} {1}", Quoter.QuoteTableName(expression.TableName, expression.SchemaName), ((Db2Column)Column).GenerateAlterClause(expression.Column)));
}
catch (NotSupportedException e)
{
return(CompatibilityMode.HandleCompatibilty(e.Message));
}
}
public override void Process(Expressions.AlterColumnExpression expression)
{
truncator.Truncate(expression);
CheckColumn(expression.TableName, expression.Column.Name);
FirebirdSchemaProvider schema = new FirebirdSchemaProvider(this);
FirebirdTableSchema table = schema.GetTableSchema(expression.TableName);
ColumnDefinition colDef = table.Definition.Columns.First(x => x.Name == quoter.ToFbObjectName(expression.Column.Name));
//Change nullable constraint
if (colDef.IsNullable != expression.Column.IsNullable)
{
PerformDBOperationExpression unSet = new PerformDBOperationExpression();
unSet.Operation = (connection, transaction) =>
{
string sql = (Generator as FirebirdGenerator).GenerateSetNull(colDef);
Announcer.Sql(sql);
using (var cmd = Factory.CreateCommand(sql, connection, transaction))
{
cmd.CommandTimeout = Options.Timeout;
cmd.ExecuteNonQuery();
}
};
FirebirdProcessedExpressionBase fbExpression = new FirebirdProcessedExpression <AlterColumnExpression>(expression, this);
if (this.FBOptions.UndoEnabled)
{
fbExpression.AddUndoExpression(unSet);
}
RegisterExpression(fbExpression);
InternalProcess((Generator as FirebirdGenerator).GenerateSetNull(expression.Column));
}
//Change default value
if (!FirebirdGenerator.DefaultValuesMatch(colDef, expression.Column))
{
IMigrationExpression defaultConstraint;
IMigrationExpression unsetDefaultConstraint;
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 (colDef.DefaultValue is ColumnDefinition.UndefinedDefaultValue)
{
unsetDefaultConstraint = new DeleteDefaultConstraintExpression()
{
ColumnName = colDef.Name,
TableName = expression.TableName,
SchemaName = expression.SchemaName
};
}
else
{
unsetDefaultConstraint = new AlterDefaultConstraintExpression()
{
ColumnName = colDef.Name,
DefaultValue = colDef.DefaultValue,
TableName = expression.TableName,
SchemaName = expression.SchemaName
};
}
FirebirdProcessedExpressionBase fbExpression = new FirebirdProcessedExpression(defaultConstraint, defaultConstraint.GetType(), this);
if (this.FBOptions.UndoEnabled)
{
fbExpression.AddUndoExpression(unsetDefaultConstraint);
}
RegisterExpression(fbExpression);
if (defaultConstraint is DeleteDefaultConstraintExpression)
{
InternalProcess(Generator.Generate(defaultConstraint as DeleteDefaultConstraintExpression));
}
else if (defaultConstraint is AlterDefaultConstraintExpression)
{
InternalProcess(Generator.Generate(defaultConstraint as AlterDefaultConstraintExpression));
}
else
{
throw new InvalidOperationException("No expression generated for alter default constraint");
}
}
//Change type
if (!FirebirdGenerator.ColumnTypesMatch(colDef, expression.Column))
{
PerformDBOperationExpression unSet = new PerformDBOperationExpression();
unSet.Operation = (connection, transaction) =>
{
string sql = (Generator as FirebirdGenerator).GenerateSetType(colDef);
Announcer.Sql(sql);
using (var cmd = Factory.CreateCommand(sql, connection, transaction))
{
cmd.CommandTimeout = Options.Timeout;
cmd.ExecuteNonQuery();
}
};
FirebirdProcessedExpressionBase fbExpression = new FirebirdProcessedExpression <AlterColumnExpression>(expression, this);
if (this.FBOptions.UndoEnabled)
{
fbExpression.AddUndoExpression(unSet);
}
RegisterExpression(fbExpression);
InternalProcess((Generator as FirebirdGenerator).GenerateSetType(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 void Process(Expressions.AlterColumnExpression expression)
{
Process(Generator.Generate(expression));
}
public override void Process(Expressions.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)
{
InternalProcess(Generator.Generate(defaultConstraint as DeleteDefaultConstraintExpression));
}
else if (defaultConstraint is AlterDefaultConstraintExpression)
{
InternalProcess(Generator.Generate(defaultConstraint as AlterDefaultConstraintExpression));
}
else
{
throw new InvalidOperationException("No expression generated for alter default constraint");
}
}
//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);
}
}
}
