static void DiffCreateTable(CreateTableStatement nextTable, List <Statement> previous, StringBuilder preForeignKeySql, StringBuilder sql, StringBuilder postForeignKeySql)
{
var previousTable = previous.Where(p => p is CreateTableStatement).Cast <CreateTableStatement>().Where(n => n.TableName == nextTable.TableName).FirstOrDefault();
if (previousTable == null)
{
WriteCreateTablePostFk(nextTable, sql, postForeignKeySql);
}
else
{
// Generate changes for columns, indices and constraints
CompareColumns(previousTable.Columns, nextTable.Columns, previousElement =>
{
// Drop
if (previousElement is TableColumn previousColumn)
{
WriteDropColumn(nextTable.TableName, previousColumn, sql);
}
else if (previousElement is TableConstraint previousConstraint)
{
WriteDropConstraint(nextTable.TableName, previousConstraint, preForeignKeySql);
}
else if (previousElement is TableKey previousKey)
{
WriteDropKey(nextTable.TableName, previousKey, sql);
}
else
{
throw new InvalidOperationException("Unhandled");
}
}, nextElement =>
{
// Add
if (nextElement is TableColumn nextColumn)
{
WriteAddColumn(nextTable.TableName, nextColumn, sql);
}
else if (nextElement is TableConstraint nextConstraint)
{
WriteAddConstraint(nextTable.TableName, nextConstraint, postForeignKeySql);
}
else if (nextElement is TableKey nextKey)
{
WriteAddKey(nextTable.TableName, nextKey, sql);
}
else
{
throw new InvalidOperationException("Unhandled");
}
}, (previousElement, nextElement) =>
{
// Modify
if (previousElement is TableColumn previousColumn && nextElement is TableColumn nextColumn)
{
// TODO: check if affects FK in separeate pass
// TODO: non-destructive alter column if possible
WriteDropColumn(nextTable.TableName, previousColumn, sql);
WriteAddColumn(nextTable.TableName, nextColumn, sql);
}
internal static void WriteCreateTable(CreateTableStatement nextTable, StringBuilder sql)
{
// Create new table with FKs
sql.AppendLine($"CREATE TABLE `{nextTable.TableName}` (");
WriteColumns(nextTable.Columns, sql);
sql.AppendLine(");");
sql.AppendLine();
}
private static void WriteCreateTablePostFk(CreateTableStatement nextTable, StringBuilder sql, StringBuilder postForeignKeySql)
{
// Create new table without FKs
sql.AppendLine($"CREATE TABLE `{nextTable.TableName}` (");
var columnsNoFk = nextTable.Columns.Where(c => !(c is TableConstraint)).ToList();
WriteColumns(columnsNoFk, sql);
sql.AppendLine(");");
sql.AppendLine();
// Put FKs in postForeignKeySql
var nextConstraints = nextTable.Columns.Where(c => c is TableConstraint).Cast <TableConstraint>().ToList();
foreach (var constraint in nextConstraints)
{
WriteAddConstraint(nextTable.TableName, constraint, postForeignKeySql);
}
}
