compileAlter method
One statement per added column, column index and command.
Implementation
List<String> compileAlter(Blueprint blueprint) {
final table = wrap(blueprint.table);
return [
for (final c in blueprint.columns)
'alter table $table add column ${compileColumn(c)}',
for (final i in blueprint.columnIndexes) compileIndex(blueprint.table, i),
for (final command in blueprint.commands)
compileCommand(blueprint.table, command),
];
}