DAX Data Analysis Expressions using Free Tools for Beginners

在Power BI中，您可能会遇到各种高级时间智能场景和商业问题，以下是针对您提供的列表中某些点的详细解释和示例：

Section 12: Advanced Time-Intelligence Scenarios

Create Date Table in DAX-0

创建DAX公式来定义一个日期表，通常是基于DATE函数或者使用DATATABLE和DATEADD等功能。

DateTable = DATATABLE(
    "Date", DATE(2021, 1, 1),
    "WeekNumber", WEEKNUM(["Date"]),
    "MonthName", FORMAT(["Date"], "MMMM"),
    "Quarter", QUARTER(["Date"]),
    MAKECOLUMNS(RELATEDTABLE())
)

Create Date Table in DAX-1

通过定义一个包含年、月、日等信息的表来创建一个更复杂的日期表。

Dates = ADDCOLUMNS(
    GENERATE(CALENDAR(2021, 1, 1), [Date], [Year], [Month], [Day]),
    "WeekNumber", WEEKNUM([Date]),
    "Quarter", QUARTER([Date]),
    "MonthName", FORMAT(DATE(YEAR([Date]), MONTH([Date]), DAY([Date])),"MMMM")
)

You work for TD (Temporary Disablement) Insurance company

如果您是为TD（暂时无能工作保险公司）工作，您可能需要处理与临时残竭相关的数据。例如，您可以创建一个DAX计算列来确定某个日期是否在员工的断崖周期内。

IsTDClaimPeriod = IF(INCLUDES(CONCATENATE('EmployeeTable'[ClaimStartDate..ClaimEndDate]), [Date]), TRUE, FALSE)

Section 13: Advanced Time-Intelligence Scenarios (Continued)

You calculate which Reseller selling what Products

使用 Power BI 的关联列和报表视图来显示销售人员和产品之间的关系。

Sales by Reseller and Product = SUMX(
    RELATEDTABLE('ResellerTable'),
    CALCULATE(
        SUM('TransactionTable'[SalesAmount]),
        FILTER(ALL('ProductTable'), 'ResellerTable'[ResellerID] IN RELATEDCOLUMNS('ProductTable') && 'ProductTable'[ProductID] IN VALUES('ResellerTable'[ProductID]))
    )
)

You calculate Best Product Sales Day

计算每个产品的销售额最高的日期。

Best Sales Day per Product = MAXX(
    ADDCOLUMNS('ProductTable', "SalesDay", SUM('TransactionTable'[SalesAmount])),
    [ProductID], _GT_[SalesAmount]
)

Dashboard-in-a-Day (Same as actual Microsoft Class)

这是一个全天候的实战课程，旨在快速构建Power BI仪表板。以下是该课程的概览：

1. Dashboard-in-a-Day and PBI Best Practices
   • 了解Power BI的最佳实践和设计原则。
2. DIAD - Introduction
   • 介绍Power BI Dashboard in a Day (DIaD) 概念和目标。
3. DIAD - Accessing Data
   • 学习如何连接到数据源，包括Excel, SQL Server, SharePoint等。
4. DIAD - Data Preparation-0
   • 清理和准备数据以便于分析。
5. DIAD - Data Preparation-1
   • 使用Power Query编辑和转换数据。
6. DIAD - Data Modeling and Exploration-0
   • 创建数据模型并进行预 exploratory analysis。
7. DIAD - Data Modeling and Exploration-1
   • 深入理解数据模型，包括定义关系和使用DAX公式。
8. DIAD - Data Modeling and Exploration-2
   • 进一步优化数据模型以提高性能和可维护性。
9. DIAD - Data Modeling and Exploration-3
   • 调试和解决数据模型中的问题。
10. DIAD - Data Modeling and Exploration-4
    • 实施高级数据模型技术，如循环引用或动态轴。
11. DIAD - Data Visualization-0
    • 创建初步的图表和仪表板。
12. DIAD - Data Visualization-1
    • 使用最佳实践来改进和优化视觉元素。
13. DIAD - Publishing Report
    • 发布报告并将其分享给团队或公众。

Section 14: Power BI Best Practices

在构建Power BI模型和仪表板时，遵循以下最佳实践：

• 数据源的管理：确保数据源的可靠性和安全性。
• 数据清洗和准备：在Power Query中处理不一致或缺失的数据。
• 模型设计：使用最小化关系模型来提高性能和可维护性。
• DAX公式：熟练使用DAX函数来计算复杂的业务逻辑。
• 视觉化：使用图表和仪表板来清晰地展示数据和洞察。
• 维护和迭代：定期检查和更新模型以确保其准确性和时效性。
• 安全性和合规性：确保数据的访问控制和隐私要求得到满足。

遵循这些最佳实践可以帮助您更有效地使用Power BI，并且能够创建强大、灵活且易于理解的数据分析工具。

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Course Review for "Mastering DAX in Power BI"

Overview: The course "Mastering DAX in Power BI" has received a global rating of 4.25 from recent reviews. The feedback is varied, with some learners appreciating the course's content and delivery, while others point out several areas for improvement. Below, we'll synthesize these reviews into key points, highlighting both the strengths and weaknesses of this online course.

Pros:

• Quality of Instruction: The instructor is commended for presenting complex concepts in an understandable manner. Their language is deemed good and easy to follow.

• Comprehensiveness: There is a demand for an "Advanced DAX" course, indicating that students find the current course comprehensive enough to warrant additional content at a higher level of difficulty.

• Practical Application: Learners appreciate the practical scenarios presented within the course, which are considered valuable in real-world applications of DAX.

• Clear Communication: Some reviews mention that the instructor has put considerable effort into packaging all DAX scenarios within one comprehensive course. The communication style is appreciated for its clarity and thoroughness.

Cons:

• Video Quality: Several reviews criticize the video quality as low, which could impact the learning experience. Users recommend adjustments to improve clarity and visual quality.

• Pacing and Clarity: There are complaints about the instructor taking too much time to explain ideas, suggesting that a faster paced delivery or more concise explanations would be beneficial. Additionally, some of the explanations are found to be unclear, particularly in sections involving complex concepts like moving averages.

• Practice Material: The lack of downloadable files or exercises for learners to practice alongside the instruction is a point of contention. Having such materials would greatly enhance the learning experience by allowing practical application in real time.

• Repetition and Errors: Some sections within the course are reported as having repetitive content, with a few lectures duplicated. Additionally, there are claims of conceptual errors within certain advanced business scenarios that need to be addressed for accuracy and clarity.

• Video Issues: A significant number of reviews mention problems playing videos, which is disappointing and detracts from the course's value.

• Pricing vs. Content Ratio: One review expresses dissatisfaction with the amount of content provided relative to the course length and price, suggesting that for a 25-hour course, there should be more practical examples and advanced content.

• Text Size and Accessibility: At least one learner points out that the text size in the videos is too small, making it difficult to see even at high resolutions like 720p. A solution such as adjustable text size options would improve accessibility.

Final Thoughts: The "Mastering DAX in Power BI" course has its strengths in instruction clarity and comprehensiveness. However, to enhance the learning experience, it would benefit from improvements in video quality, pacing, the inclusion of downloadable materials for practice, and ensuring that all content is both accurate and error-free. Addressing these issues could significantly improve the overall rating and value of this course for learners.

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Note to Future Students: When considering this course, be aware that while many find it valuable, there are notable issues with video quality and clarity in some sections. If you prefer a course with clear visuals, more practice opportunities, and a faster paced learning experience, you may want to explore alternative options or request updates from the course provider regarding improvements made since these reviews were collected.