Validates and deletes a column in a table in schema.
Source
void deleteColumn(String tableName, String columnName) {
var table = schema.tableForName(tableName);
if (table == null) {
throw new SchemaException("Table $tableName does not exist.");
}
var column = table.columnForName(columnName);
if (column == null) {
throw new SchemaException("Column $columnName does not exists.");
}
table.removeColumn(column);
if (store != null) {
commands.addAll(store.deleteColumn(table, column));
}
}