I’m working with .xlsx files that were exported from Google Sheets using PHPSpreadsheet library. The problem is that when I call $activeSheet->getHighestColumn() and $activeSheet->getHighestRow() methods, they return huge values like column Z and row 1000, even though my actual data only goes to maybe column D and row 50.
It seems like Google Sheets pre-allocates a large grid when exporting, unlike regular Excel files where these methods work correctly. These “empty” cells appear truly blank when I open the file in Excel or Google Sheets.
This creates a performance issue because I need to loop through all rows to process my data. With the inflated dimensions, I end up processing thousands of empty rows which wastes memory and time.
Is there a more efficient way to find the actual last row and column that contain real data? Right now I have to manually iterate through everything and check if cells are genuinely empty, but this feels like overkill for what should be a simple operation.
Had this exact problem with Google Sheets batch exports at my last job. What worked best was using PHPSpreadsheet’s getUsedRange() method instead of getHighestRow() and getHighestColumn(). It only grabs the actual data range, which massively boosted performance. I also tried reverse iteration - started from a reasonable max row estimate and worked backwards until hitting the first non-empty cell. Cut processing time by about 80% compared to going forward through all those phantom rows Google Sheets dumps into exports.
I encountered similar issues with large Google Sheets exports. One method that proved effective was implementing a two-pass approach. In the first pass, I scanned the rightmost column, checking every 10th or 20th row to determine where my data actually ends. Then, I performed the same check for rows by examining the bottom columns. This helped establish real boundaries before conducting a full loop. Additionally, setting practical limits based on my data knowledge significantly improved performance, making it a solid strategy for processing multiple files.
for sure! it’s such a pain dealing with those empty rows. starting from the highest row works way better, saves a lot of time and hassle! totally get where you’re coming from, been there too!