榜单
讯飞星火
服务器优惠
IT文库
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LOWER
lower description Syntax example keywords lower description Syntax VARCHAR lower(VARCHAR str) 将参数中所有的字符串都转换成小写，该函数的另一个别名为lcase 。 example mysql > SELECT lower ( "AbC12... -
Data model
Data Model Narrow-table Model Wide-table Model JOINs with Relational Data Data Model As a relational database supporting full SQL, TimescaleDB supports flexible data models ... -
$project (aggregation)
$project (aggregation) Definition Considerations Include Existing Fields Suppress the _id Field Exclude Fields Exclude Fields Conditionally Add New Fields or Reset Existing Fi... -
CloudFront
CloudFront CloudFront CloudFront LocalStack Pro supports creation of local CloudFront distributions, which allows you to transparently access your applications and file artifac... -
Troubleshoot the Map Function
Troubleshoot the Map Function Troubleshoot the Map Function The map function is a JavaScript function that associates or “maps”a value with a key and emits the key and value p... -
修改密码
用于修改OceanBase登录用户的密码。 格式 SET PASSWORD [ FOR user =] password_option ; password_option : { PASSWORD (‘ authstring ’) |’ hashstring ’ } ... -
lower
lower Description Syntax example keyword LOWER lower Description Syntax ‘INT lower (WARCHAR str)’ Convert all strings in parameters to lowercase example mysql > SE... -
$project
$project 1. 指定输出字段 2. 输出嵌入式文档中field 3. 改变输出结构 4. 计算 Fields $project 修改输入文档的结构。可以用来重命名、增加或删除字段(域)，也可以用于创建计算结果以及嵌套文档。 思考，现有books集合内容如下： db . books . insert ( { "_id"... -
$literal (aggregation)
$literal (aggregation) Definition Behavior Examples Treat $ as a Literal Project a New Field with Value 1 $literal (aggregation) Definition $literal Returns a value w... -
用户管理
用户管理 用户管理 PinusDB用户角色分为readOnly、writeOnly、readWrite以及admin。 readOnly用户只能查询数据（不包括系统表）。 writeOnly用户只能向数据表写入数据（不包括系统表）。 readWrite用户可以查询并写入数据（不包括系统表）。 admin 用户可以执行所有操作。 1. 查...