Merged and multi-row headers

• The sheet was laid out as a report for people to read, with a banner heading over groups of columns.
• Cells were merged for appearance, which leaves every cell but the first one empty.
• A title, a date, or a logo row sits above the real header.

• Software takes the first row as the header, so columns are named after a banner or left unnamed.
• The second header row is read as data, which turns numeric columns into text.
• Columns under a merged heading lose it, and two columns both called q1 cannot be told apart.

• Look at the first few rows for merged cells, empty header cells, and repeated names.
• Check whether the first row of data holds labels instead of values.
• After importing, look for columns with generated names or numbers where names should be.

• Fill each merged heading across the columns it covered.
• Combine the header rows into one name per column, joining the levels in a consistent order.
• Remove title and decoration rows from the table, and keep what they said, such as the reporting period, in a column or in the file's documentation.
• Check that every resulting name is unique.

• Totals and notes rows inside the dataRows that are not records, such as subtotals, grand totals, and footnotes, sit among the rows that are.
• Wide tables that should be longValues of one variable, such as months or years, are spread across the column headers instead of being stored in a column of their own.
• Inconsistent column names across filesFiles that should share one layout name the same column differently, or use the same name for different things.

TermsHeader, Schema, Tidy data, Tabular data