Theory
The sort that scrambled everything
Meera wants her stock list ordered from lowest quantity to highest, so shortages jump to the top. She clicks the quantity column, hits Sort, and disaster: the quantities reorder but the item names do not. Now 'Sugar' shows a quantity that belongs to 'Rice'. Her whole sheet is nonsense.
She made the single most common Excel mistake, and it is entirely avoidable. Sorting and filtering are how you find what matters in a big table, if you do them right. The right way is this lesson.
Theory
Reseating a class, together
Sorting a table is like reseating a class by exam rank. Done right, each student moves to a new bench carrying their bag, books and water bottle, everything travels together. Meera's mistake was moving only the rank cards while students stayed put, so now the wrong card sits on the wrong desk. When you sort, the whole row must move as one, or the data lies.
Theory
Sorting, done right
Sort reorders rows by a chosen column, ascending (A to Z, small to large) or descending.
The golden rule: select the entire table (or just click one cell inside it and use Data > Sort, which auto-detects the whole block). Then Excel moves complete rows together, keeping every item with its own price and quantity.
Multi-level sort: sort by category first, then by sales within each category, so ties break sensibly. Data tab > Sort lets you add levels.
Theory
Filtering: hide, do not delete
Filter (Data > Filter) adds a small dropdown arrow to each heading. Click it and tick which values to show; everything else is temporarily hidden.
- Filter by value: show only 'Tea' rows.
- Filter by condition: show only quantity below 10.
The hidden rows are not deleted, they are just out of view. Clear the filter and they all return. Filtering is asking your table a question and seeing only the answers.
Quiz
Meera selects ONLY the quantity column and sorts it ascending. What happens to her table?
- The quantities reorder but names/prices stay put, scrambling which value belongs to which item
- The whole table sorts correctly
- Excel refuses and shows an error every time
- Only the column header changes
Show the answer
The quantities reorder but names/prices stay put, scrambling which value belongs to which item
Sorting a single column in isolation moves only those values while the other columns stay fixed, so rows break apart and data becomes wrong. Always sort the whole table (or click one cell and let Excel select the block). Excel may warn you, but if you 'continue with current selection' it scrambles silently. This is the number-one sorting trap in exams and offices.
Think first
Filtered, not gone
Meera filters her 500-row sheet to show only items below 10 units, and sees just 12 rows. She panics that the other 488 rows are deleted. Are they? What should she do to bring them back?
Show the answer
Not deleted, just hidden. Filtering only conceals non-matching rows; the 488 are safe and their data intact. To restore them, she clears the filter (Data > Clear, or untick the condition). Filtering is a temporary view, not a delete, the same 'hide vs delete' idea as hiding columns last unit. Nothing is lost.
Watch out
Where marks leak
The big one: sorting one column alone scrambles rows, always sort the whole table. Thinking a filter deletes the hidden rows, it only hides them (clear to restore). Forgetting multi-level sort exists for tie-breaking. And note ascending (small-to-large, A-Z) vs descending, exams sometimes ask which order puts the largest value on top (answer: descending).
Theory
You are previewing SQL
Hold this thought: sorting is exactly SQL's ORDER BY and filtering is exactly SQL's WHERE, the two commands you will write constantly in Unit 4 and in every database job. Excel lets you click what you will later type. When you reach SQL, filtering and sorting will feel like old friends in a new language. Next: splitting messy columns and removing duplicate rows.
Summary
Key takeaways
- Sort reorders rows by a column; ALWAYS include the whole table so rows stay together.
- Sorting one column alone scrambles the data, the number-one trap.
- Multi-level sort (by category, then sales) breaks ties sensibly.
- Filter adds header dropdowns to show only matching rows; non-matches are HIDDEN, not deleted.
- Clear the filter to bring every row back.
- Memory hook: sorting = reseat the class with their bags; filtering = ORDER BY / WHERE previewed.