CSV
Fixing Expected Columns but Found Errors in SQLite Imports
SQLite prints expected N columns but found M and loads the row anyway, with exit status zero. See each import message and what it did to the data.
7 min read
Library
Everything you need to level up your coding skills.
CSV
Exporting a SQLite Query Result to CSV From the Shell
Export a SQLite query to CSV with the shell, see exactly how 3.54 quotes values, writes NULL and ends lines, and learn which options change each.
8 min read
CSV
Querying a CSV File in SQLite Without Importing It
Compile SQLite's CSV virtual table, query a file in place, and compare the cost with importing it and with DuckDB, including the typed schema surprises.
6 min read
CSV
Importing a CSV Into an Existing SQLite Table Step by Step
Importing into a table that holds data goes wrong four ways: duplicate keys, missing columns, extra columns and a new order. See each and the staging fix.
7 min read
CSV
Setting Column Types When SQLite Imports a CSV File Safely
sqlite3 .import makes untyped columns. Create the table yourself, choose between INTEGER, TEXT and STRICT, and see what a ZIP code and a bad price do in each.
7 min read
CSV
Using the sqlite3 dot import Command With a CSV File
Every option of the sqlite3 .import command that matters for CSV, from --csv and --skip to --schema temp and piped input, with the output of each.
7 min read
Editor's pick
CSVGuide
Importing CSV Files Into SQLite From the Command Line
The sqlite3 .import command loads a CSV in seconds and reports problems as warnings with exit status zero. Import safely with types, checks and a swap.
20 min read
Excel
Validating Row Counts After an Excel Import Step by Step
Prove an Excel import lost nothing by counting rows at the source, the stage and the target, adding control totals, and reconciling rejects in one query.
8 min read
Excel
Staging Excel Data in a Table Before Cleaning It Up
Design a staging table for Excel loads with text columns and provenance, load it fast, profile it with SQL and keep or drop it on a retention rule.
8 min read
Excel
Loading Excel Files With DuckDB and the Excel Extension
Query an XLSX sheet with SQL in DuckDB through its excel extension, read every column as text, create a table and copy it to PostgreSQL or Parquet.
8 min read
Excel
Importing Excel Dates Correctly Into a Date Column
An Excel date column holds serial numbers, real dates or text. Classify each value in the stage, convert each kind by an explicit rule and reject the rest.
7 min read
Excel
Handling Excel Files With Title Rows Above the Header
Find the real header row in an Excel sheet with a title, a date line or a logo above it, read from there with pandas, and cut notes and totals off the bottom.
7 min read
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