更新时间:2021-08-09 07:01:24
如果你想在数据库不存在的情况下创建它,或者如果它存在就得到一个类似数据库已经存在"的值,你可以这样做以下内容:
If you want to create a database if it does not exists, or get a value like "database already exists" if it does exist, you could do something like the following:
r.dbList().contains('example_database')
.do(function(databaseExists) {
return r.branch(
databaseExists,
{ dbs_created: 0 },
r.dbCreate('example_database')
);
}).run();
如果它被创建将返回以下内容:
It will return the following if it is created:
{
"config_changes": [
{
"new_val": {
"id": "1ee7ddb4-6e2c-43bb-a0f5-64ef6a6211a8",
"name": "example_database"
},
"old_val": null
}
],
"dbs_created": 1
}
如果它已经存在:
{
"dbs_created": 0
}