func addIndex(indexName string, table *core.Table, col *core.Column, indexType int) {
if index, ok := table.Indexes[indexName]; ok {
index.AddColumn(col.Name)
col.Indexes[index.Name] = indexType
} else {
index := core.NewIndex(indexName, indexType)
index.AddColumn(col.Name)
table.AddIndex(index)
col.Indexes[index.Name] = indexType
}
}
