Comma-Separated Values (.csv)
RFC StandartsComma-Separated Values (CSV) is a ubiquitous plain-text format for tabular data, where each line represents a data record and fields are separated by delimiter characters.
Konvertēt XLSX uz CSV
Bezmaksas XLSX uz CSV konvertētājs pārlūkprogrammā. Konvertējiet failus uzreiz savā ierīcē.
Saspiest CSV tiešsaistē
100% privāta saspiešana pārlūkprogrammā – faili nekad nepamet jūsu ierīci
Pārbaudīt un metadati
Operētājsistēmas un failu analizatori identificē CSV failus, pārbaudot sākotnējo bināro baitu secību:
Baitu līmeņa galvenes paraksts (maģiskie baiti)
Operētājsistēmas un failu analizatori identificē CSV failus, pārbaudot sākotnējo bināro baitu secību:
HEKSADECIMĀLAIS PARAKSTS (NOBĪDE 0):
Plain TextASCII ATTEIOLOJUMS: ASCII / UTF-8
Standartizācija: RFC 4180 / IETF
Tehniskās specifikācijas
| Konteinera arhitektūra | Delimited flat text file representing tabular data rows and columns |
| Saspiešana | Gzip / Deflate achieves 85%-95% compression on repetitive tabular records |
| Baitu secība | UTF-8 text stream (optional UTF-8 BOM EF BB BF used by Excel) |
| Krāsu telpas | Not applicable |
| Kanāli un struktūra | Row records delimited by CRLF with columns delimited by commas |
| Maks. izmēri | Unbounded; streamable to gigabytes without loading entire file in memory |
| Caurspīdīgums | Not applicable |
| Straumēšana un progresīvā ielāde | Native line-by-line stream processing supported by all data pipelines |
Tehniskā salīdzinājuma matrica: CSV pret konkurentiem
| Tehniskais atribūts | CSV (Pašreizējais) | Excel (XLSX) | Parquet | JSON |
|---|---|---|---|---|
| File Type | Plain text flat table | Zipped XML spreadsheet | Binary columnar storage | Hierarchical text |
| Multiple Sheets | No (single flat table only) | Yes (multiple workbooks and sheets) | Partition-based storage | Nested arrays and objects |
| Data Types | Untyped raw text | Typed cells, formulas, formatting | Strict binary column types | Primitive types (string, number, bool) |
| Big Data Analytics | Slow (requires reading every row linearly) | Not suitable for big data | Ultra-fast (column pruning & predicate pushdown) | Moderate |
Biežākie bojājumu veidi un heksadecimālās atkopšanas ceļvedis
⚠️ Columns shift to the right or row counts do not match.
Pamatcēlonis: A text field containing an unescaped comma without surrounding quotation marks.
Atkopšana: RFC 4180 requires fields containing commas to be wrapped in double quotes: "Smith, John".
⚠️ Accented characters render as strange symbols (mojibake like é instead of é) in Excel.
Pamatcēlonis: Excel opened a UTF-8 CSV assuming the legacy Windows ANSI/CP1252 character encoding.
Atkopšana: Prepend the 3-byte UTF-8 Byte Order Mark (0xEF 0xBB 0xBF) to the beginning of the file.
Drošības analīze un parsētāja uzbrukuma vektori
CSV files open directly in spreadsheet software like Excel and Google Sheets, exposing users to Formula Injection (CSV Injection) attacks.
Zināmie uzbrukuma vektori
- Formula Injection: Cells starting with '=', '+', '-', or '@' executing spreadsheet macros or DDE commands (e.g. '=cmd|' /C calc'!A0').
- Data exfiltration via HYPERLINK() formulas sending sensitive cell data to remote attacker servers upon click.
Aizsardzības labākā prakse: When exporting user data to CSV, prepend a single quote (') or tab to any cell starting with '=', '+', '-', or '@' to force plain text rendering in Excel.
Vēsturiskā izcelsme un pavērsieni
Galvenās priekšrocības un plusi
- Maximum simplicity: readable in any text editor and importable into every database and spreadsheet.
- Extremely fast line-by-line streaming without building a full in-memory DOM.
- Minimal overhead: no verbose tag syntax or schema definitions.
Tehniskie ierobežojumi un mīnusi
- No standard data types: numbers, dates, booleans, and text are all stored as raw strings.
- No support for multiple sheets, cell formatting, formulas, or metadata.
- Delimiter conflicts (commas inside text, decimal commas in European locales) cause frequent parsing bugs.
Interesanti tehniski fakti
- In many European countries where commas are used as decimal points, semicolons (;) are used instead of commas as CSV separators.
- Microsoft Excel historically required a UTF-8 BOM (0xEF 0xBB 0xBF) to correctly display non-ASCII accented characters.
Bieži uzdotie tehniskie jautājumi
What is RFC 4180?
RFC 4180 is the official IETF standard for CSV. It mandates that fields containing commas, line breaks, or double quotes must be enclosed in double quotes, and internal quotes must be escaped by doubling them ("").
Why do CSV files open with corrupted characters in Excel?
Older versions of Microsoft Excel default to the local Windows code page (like Windows-1252) rather than UTF-8 when opening CSV files directly. Adding a UTF-8 BOM (Byte Order Mark) at the start of the file forces Excel to decode UTF-8 correctly.
Saistītie CSV konvertēšanas pāri
Export Microsoft Excel spreadsheets into clean, comma-separated plain text tables.
Import CSV tabular data into formatted Microsoft Excel XLSX workbooks.
Import tabular CSV spreadsheet records directly into indexed SQLite database tables.
Extract table records and rows from SQL INSERT statements into standardized comma-separated CSV spreadsheets.
Extract multidimensional scientific datasets and numerical matrices from HDF5 (.h5) into tabular CSV format.
Flatten multidimensional NetCDF (.nc) climate and oceanographic variables into comma-separated CSV spreadsheets.
Convert electronic business cards (vCard / VCF) into tabular CSV contact lists for Excel and Google Contacts.