1.创建索引语法
create index index_name on table_name(column1);

例如：create index 'idx_quotation_createdByUsername' on quotation("createdByUsername");

2.创建组合索引
create index 'idx_quotation_createdByUsername' on quotation("createdByUsername","createdBy");

3.唯一索引
create unique index 'idx_quotation_createdByUsername' on quotation("createdByUsername","createdBy");

4.删除索引

drop index 'idx_quotation_createdByUsername';