میخواهیم نوع ستون second را از string به float برای تمام داکیومنت ها (رکوردها) تغییر دهیم مراحل زیر را طی میکنیم:
1-
PUT _ingest/pipeline/convert-call-seconds-to-float
{
"description": "converts the content of the second field to an float",
"processors" : [
{
"convert" : {
"field" : "second",
"type": "float",
"ignore_missing": true
}
}
]
}
2-
POST /db_name/_update_by_query?pipeline=convert-call-seconds-to-float
مرجع:
In programming, we often remove the spaces between words because programs of different sorts reserve the space (‘ ’) character for special purposes. Because the space character is reserved, we cannot use it to represent a concept that we express in our human language with multiple words. As an example, the concept of “user login count” is not referenced in our code as “user login count” often. We do not do the following:
user login count = 5;
A typical language parse would treat each word as a separate concept. “User,” “login,” and “count” would each be treated as separate things. So, we do something like the following:
userLoginCount = 5;
Now, the parser will see one concept — “userLoginCount” — and us programmers can easily see the representation.
There is no best way to combine words. In the above example, we removed spaces and capitalized the each word following the first word. There are, however, a great number of algorithms for combining words, and a few very common ones.
The commonly used strategies for combining words are: camel case, pascal case, snake case, and kebab case. We’ll go over those here.
Camel case combines words by capitalizing all words following the first word and removing the space, as follows:
Raw: “user login count”
Camel Case: “userLoginCount”
This is a very popular way to combine words to form a single concept and is often used as a convention in variable declaration in many languages.
Pascal case combines words by capitalizing all words (even the first word) and removing the space, as follows:
Raw: “user login count”
Pascal Case: “UserLoginCount”
This is also very popular way to combine words to form a single concept and is often used as a convention in declaring classes in many languages.
Snake case combines words by replacing each space with an underscore (‘_’) and, in the “all caps” version, all letters are capitalized, as follows:
Raw: “user login count”
Snake Case: “user_login_count”
Snake Case (All Caps): ”USER_LOGIN_COUNT”
This style when capitalized often used as a convention in declaring constants on in many languages. When lower cased, it used conventionally in declaring database field names.
Kebab case combines words by replacing each space with a dash (‘-’), as follows:
Raw: “user login count”
Kebab Case: “user-login-count”
This style is often used in URLs, for example, “www.blog.com/cool-article-1”. It is a nice, clean, human readable way to combine the words.
There is no best method of combining words. The main thing is to be consistent with the convention used, and, if you’re in a team, to come to an agreement on the convention together.
thanksForReading!
ThanksForReading!
THANKS_FOR_READING_!
thanks-for-reading-!
Cheers!
Resource :
هر جزء فیزیکی یا مجازی با دسترسی محدود در سیستم کامپیوتری است
URI :Uniform Resource Identifier
تعاریف URI
- توالی پیوسته ای از کارکترهاست برای شناسایی یه منبع(Resource ) فیزیکی یا انتزاعی.
- رشته ای است که به یک منبع اشاره دارد.
URI = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
hier-part = "//" authority path-abempty
/ path-absolute
/ path-rootless
/ path-empty