Now let’s create an index named "customer" and then list all the indexes again: 现在让我们创建一个名为“customer”的索引,然后再次列出所有索引: PUT /customer?pretty GET /_cat/indices?v The first command creates the index named "customer" using the PUT verb. We s…

FATAL: UNABLE TO CREATE ‘…GIT/INDEX.LOCK’ FILE EXISTS Hi, Today I will share you my other experience using git control system, it happened to me after I’ve created a branch, when adding my changes to remote or even committed my file I’ve started to s…

更改实体对应表结构失败[修改实体对象表结构失败[修改表[tSysParam]的主键信息失败:CREATE UNIQUE INDEX 终止,因为发现对象名称 'dbo.tSysParam' 和索引名称 'PK_tSysParam' 有重复的键.重复的键值为 (6).]] 这种问题是由于主键设置了唯一性,而数据库中主键列的值又有重复的值,为6,改掉其中一个值就可以 了.…

db.collection.createIndex( { name: -1 } ) Indexes — MongoDB Manual https://docs.mongodb.com/manual/indexes/ The following example creates a single key descending index on the name field: db.collection.createIndex( { name: -1 } ) The db.collection.cre…

Git – fatal: Unable to create ‘/.git/index.lock’: File exists. fatal: Unable to create ‘/path/my_proj/.git/index.lock’: File exists. If no other git process is currently running, this probably means a git process crashed in this repository earlier. M…

有时候在提交的时候,中间提交出错,导致有文件被lock,所以会报下面的错误: fatal: Unable to create ‘/msg/.git/index.lock’: File exists. If no other git process is currently running, this probably means a git process crashed in this repository earlier. Make sure no other git process is…

执行PgSql避免 notice 信息,执行之前加入以下语句调整报错级别即可: SET CLIENT_MIN_MESSAGES = ‘WARNING’;…

这种问题是由于主键设置了唯一性,而数据库中主键列的值又有重复的值,重复值为E,改掉其中一个值就可以了.…

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创建和删除索引索引的创建可以在CREATE TABLE语句中进行,也可以单独用CREATE INDEX或ALTER TABLE来给表增加索引.删除索引可以利用ALTER TABLE或DROP INDEX语句来实现.(1)使用ALTER TABLE语句创建索引.语法如下:alter table table_name add index index_name (column_list) ;alter table table_name add unique (column_list) ;alter t…