https://pbidocs.com/blog Practical fixes, cheat sheets, and end-to-end tutorials for Power BI, DAX, and Power Query. en-us https://pbidocs.com/blog/refresh-suddenly-slow-query-folding-broke https://pbidocs.com/blog/refresh-suddenly-slow-query-folding-broke A refresh that used to take seconds and now takes minutes, with no error and no obvious cause, almost always means query folding silently broke somewhere. Here's how to find exactly which step, and the four usual causes. Sun, 23 Aug 2026 00:00:00 GMT Power Query Troubleshooting https://pbidocs.com/blog/couldnt-convert-to-number-date-error https://pbidocs.com/blog/couldnt-convert-to-number-date-error "DataFormat.Error: We couldn't convert to Number" (or Date) usually isn't bad data — it's a locale mismatch, hidden whitespace, or a stray non-numeric value. Here's how to find which, and the fix for each. Sat, 22 Aug 2026 00:00:00 GMT Power Query Troubleshooting https://pbidocs.com/tutorials/build-an-evm-dashboard https://pbidocs.com/tutorials/build-an-evm-dashboard An end-to-end tutorial for systems and program engineers: turn a task list into real CPI, SPI, and EAC measures in DAX, using a disconnected date table to project planned value over time. Fri, 21 Aug 2026 00:00:00 GMT Tutorial DAX Data Modeling Tutorial https://pbidocs.com/blog/formula-firewall-privacy-level-error https://pbidocs.com/blog/formula-firewall-privacy-level-error "Formula.Firewall: Query references other queries or steps, so it may not directly access a data source" comes from Power Query's privacy level checks, not a bug in the query. Here's what triggers it and how to fix it properly. Thu, 20 Aug 2026 00:00:00 GMT Power Query Troubleshooting https://pbidocs.com/tutorials/build-a-fabric-lakehouse-dashboard https://pbidocs.com/tutorials/build-a-fabric-lakehouse-dashboard An end-to-end Microsoft Fabric tutorial: land raw usage events in a Lakehouse, clean and shape them with a notebook into a star schema, connect Power BI in Direct Lake mode, and build a report — no Import refresh involved. Wed, 19 Aug 2026 00:00:00 GMT Tutorial Fabric Data Modeling DAX Tutorial https://pbidocs.com/blog/dax-calculate-modifiers-cheat-sheet https://pbidocs.com/blog/dax-calculate-modifiers-cheat-sheet A fast, scannable reference for the filter-modifying functions used inside CALCULATE — ALL, ALLEXCEPT, ALLSELECTED, REMOVEFILTERS, KEEPFILTERS, and USERELATIONSHIP. Mon, 17 Aug 2026 00:00:00 GMT DAX Cheat Sheet https://pbidocs.com/blog/couldnt-load-data-for-this-visual https://pbidocs.com/blog/couldnt-load-data-for-this-visual "Couldn't load the data for this visual" is a generic banner covering several unrelated causes. Here's how to read the real error underneath it, and the four usual culprits. Sun, 16 Aug 2026 00:00:00 GMT Power BI Service Troubleshooting https://pbidocs.com/blog/single-value-column-cannot-be-determined https://pbidocs.com/blog/single-value-column-cannot-be-determined This error means a measure referenced a column directly instead of aggregating it. Here's why it often works at the row level and breaks at the total, and how to fix it. Sat, 15 Aug 2026 00:00:00 GMT DAX Troubleshooting https://pbidocs.com/blog/key-didnt-match-any-rows-error https://pbidocs.com/blog/key-didnt-match-any-rows-error "The key didn't match any rows in the table" comes from LOOKUPVALUE finding zero matches, not too many. Here's how to find why, and the four usual causes. Fri, 14 Aug 2026 00:00:00 GMT DAX Troubleshooting https://pbidocs.com/blog/column-contains-duplicate-value-error https://pbidocs.com/blog/column-contains-duplicate-value-error "The column 'X' in table 'Y' contains a duplicate value" happens when you try to build a relationship on a column that isn't actually unique. Here's how to find and fix the duplicates. Thu, 13 Aug 2026 00:00:00 GMT Data Modeling Power Query Troubleshooting https://pbidocs.com/tutorials/build-a-sales-analysis-report https://pbidocs.com/tutorials/build-a-sales-analysis-report An end-to-end Power BI tutorial: clean raw sales data in Power Query, model it as a star schema, write real DAX measures, and lay out a report — using one consistent dataset from start to finish. Wed, 12 Aug 2026 00:00:00 GMT Tutorial Power Query Data Modeling DAX Tutorial https://pbidocs.com/blog/dax-time-intelligence-cheat-sheet https://pbidocs.com/blog/dax-time-intelligence-cheat-sheet A fast, scannable reference for the DAX time intelligence functions you'll actually reach for — YTD, prior period, and period-over-period comparisons. Mon, 10 Aug 2026 00:00:00 GMT DAX Cheat Sheet https://pbidocs.com/blog/fix-circular-dependency-dax https://pbidocs.com/blog/fix-circular-dependency-dax "A circular dependency was detected" usually comes from a calculated column, not a measure. Here's how to find the cycle and break it. Mon, 10 Aug 2026 00:00:00 GMT DAX Troubleshooting https://pbidocs.com/blog/power-query-expression-error-field-not-found https://pbidocs.com/blog/power-query-expression-error-field-not-found This error means a step is referencing a column name that doesn't exist by the time it runs. Here's how to find which step, and the four usual causes. Mon, 10 Aug 2026 00:00:00 GMT Power Query Troubleshooting