A core capability of Power Query is to filter and combine, that is, to mash-up data from one or more of a rich collection of supported data sources. Any such data mashup is expressed using the Power Query M formula language. The M language is …

2025年1月27日 · To create an M query in the advanced editor, you follow this basic process: Create a series of query formula steps that start with the let statement. Each step is defined by a step variable name.

2024年3月29日 · The Power Query M function reference includes articles for each of the over 700 functions. These reference articles are auto-generated from in-product help. To learn more about functions and how they work in an expression, go to Understanding Power Query M functions .

Any such data mashup is expressed using the Power Query formula language (informally known as "M"). Power Query embeds M documents in a wide range of Microsoft products, including Excel, Power BI, Analysis Services, and Dataverse, to enable repeatable mashup of data.

2024年3月29日 · If the value produced by evaluating the if-condition is not a logical value, then an error with reason code "Expression.Error" is raised. The true-expression is only evaluated if …

2025年3月18日 · Connect to a secure URL that accepts an authentication key as part of its query string. Instead of hard-coding the secret key in M (which would pose a security risk), the key can be provided securely by specifying its name (not its value) in M, choosing Web API authentication, and entering the key value as part of the Web API credential.

2022年8月8日 · An M document is an ordered sequence of Unicode characters. M allows different classes of Unicode characters in different parts of an M document. For information on Unicode character classes, see The Unicode Standard, Version 3.0, section 4.5. A document either consists of exactly one expression or of groups of definitions organized into ...

Returns the M source code representation of a constant value. Expression.Evaluate: Returns the result of evaluating an M expression. Expression.Identifier: Returns the M source code representation of an identifier.

The following table summarizes the M operators, listing the operator categories in order of precedence from highest to lowest. Operators in the same category have equal precedence.

2025年3月18日 · In this article Syntax Text.Length(text as nullable text) as nullable number About. Returns the number of characters in the text text.. Example 1. Find how many characters are in the text "Hello World".