Fixed width files

fixed parse fixed parse fixed read fixed read fixed format fixed format fixed write fixed write

fixed parse <text> <json_layout>

Description

Read fixed width text into rows

Parameters

text: The text - String - required
json_layout: The layout - String - required

admin
fixed parse "41100001Dupont SA   000125050-20261031
41100002Martin      000008990020261102
" "[{\"name\": \"account\", \"length\": 8}, {\"name\": \"label\", \"length\": 12}, {\"name\": \"amount\", \"length\": 10, \"type\": \"decimal\", \"decimals\": 2, \"sign\": \"trailing\"}, {\"name\": \"date\", \"length\": 8, \"type\": \"date\"}]"

mentdb
[{"account": "41100001", "label": "Dupont SA", "amount": -1250.5, "date": "2026-10-31"}, {"account": "41100002", "label": "Martin", "amount": 899, "date": "2026-11-02"}]

fixed parse <text> <json_layout> <json_params>

Description

Read fixed width text with parameters (skip, skip_trailer, record_length, strict, on_error, encoding)

Parameters

text: The text - String - required
json_layout: The layout - String - required
json_params: The parameters - String - required

admin
fixed parse "HEADER 20261103
01F0000104ACME      
02CABLE 0020001050
02SWITCH0010004900
TRAILER 3
" "{\"record_type\": {\"start\": 1, \"length\": 2}, \"layouts\": {\"01\": [{\"name\": \"invoice\", \"start\": 3, \"length\": 8}, {\"name\": \"customer\", \"length\": 10}], \"02\": [{\"name\": \"item\", \"start\": 3, \"length\": 6}, {\"name\": \"qty\", \"length\": 3, \"type\": \"int\"}, {\"name\": \"price\", \"length\": 7, \"type\": \"decimal\", \"decimals\": 2}]}}" "{\"skip\": 1, \"skip_trailer\": 1}"

mentdb
[{"_type": "01", "invoice": "F0000104", "customer": "ACME"}, {"_type": "02", "item": "CABLE", "qty": 2, "price": 10.5}, {"_type": "02", "item": "SWITCH", "qty": 1, "price": 49}]

Records without line breaks

admin
fixed parse "AB12CD34EF56" "[{\"name\": \"code\", \"length\": 2}, {\"name\": \"n\", \"length\": 2, \"type\": \"int\"}]" "{\"record_length\": 4}"

mentdb
[{"code": "AB", "n": 12}, {"code": "CD", "n": 34}, {"code": "EF", "n": 56}]

Used in use cases (1 recipe)

Integrator & ETL developer › Read a mainframe fixed width export with header, trailer and two record types

Often used with

csv from_json · equal · json doc · json iarray

fixed read <path> <json_layout>

Description

Read a fixed width file into rows

Parameters

path: The file path - String - required
json_layout: The layout - String - required

admin
if (equal (file exist "tmp/tuto_etl") "0") {file mkdir "tmp/tuto_etl";};
file create "tmp/tuto_etl/in.txt" "A0001 012
A0002 007
";
-> "[res]" (fixed read "tmp/tuto_etl/in.txt" "[{\"name\": \"code\", \"length\": 5}, {\"name\": \"qty\", \"length\": 4, \"type\": \"int\"}]");
file delete "tmp/tuto_etl/in.txt";
[res]

mentdb
[{"code": "A0001", "qty": 12}, {"code": "A0002", "qty": 7}]

fixed read <path> <json_layout> <json_params>

Description

Read a fixed width file with parameters

Parameters

path: The file path - String - required
json_layout: The layout - String - required
json_params: The parameters - String - required

admin
-> "[layout]" "[{\"name\": \"code\", \"length\": 5}, {\"name\": \"qty\", \"length\": 4, \"type\": \"int\"}]";
if (equal (file exist "tmp/tuto_etl") "0") {file mkdir "tmp/tuto_etl";};
file create "tmp/tuto_etl/stock.txt" "STOCK 2026-11-03
A0001 012
A0002 0x7
A0003 105
END
";
-> "[res]" (fixed read "tmp/tuto_etl/stock.txt" [layout] "{\"skip\": 1, \"skip_trailer\": 1, \"on_error\": \"skip\"}");
file delete "tmp/tuto_etl/stock.txt";
[res]

mentdb
{"rows": [{"code": "A0001", "qty": 12}, {"code": "A0003", "qty": 105}], "rejected": ["line 3: field 'qty': '0x7' is not a number"]}

fixed format <json_rows> <json_layout>

Description

Write rows as fixed width text: numbers right-aligned and zero padded, texts left-aligned; a value too long is an error

Parameters

json_rows: The rows - String - required
json_layout: The layout - String - required

admin
fixed format "[{\"account\": \"41100001\", \"label\": \"Dupont SA\", \"amount\": -1250.5, \"date\": \"2026-10-31\"}, {\"account\": \"41100002\", \"label\": \"Martin\", \"amount\": 899, \"date\": \"2026-11-02\"}]" "[{\"name\": \"account\", \"length\": 8}, {\"name\": \"label\", \"length\": 12}, {\"name\": \"amount\", \"length\": 10, \"type\": \"decimal\", \"decimals\": 2, \"sign\": \"trailing\"}, {\"name\": \"date\", \"length\": 8, \"type\": \"date\"}]"

mentdb
41100001Dupont SA   000125050-20261031
41100002Martin      000008990020261102

fixed format <json_rows> <json_layout> <json_params>

Description

Write fixed width text with parameters: truncate (cut the values too long), replace_newlines (a line break in a value becomes a space, refused otherwise), line_end (lf, crlf or none), encoding (checks that every character can be written)

Parameters

json_rows: The rows - String - required
json_layout: The layout - String - required
json_params: The parameters - String - required

admin
fixed format "[{\"code\": \"A1\", \"label\": \"A very long product label\"}]" "[{\"name\": \"code\", \"length\": 4}, {\"name\": \"label\", \"length\": 10}]" "{\"truncate\": true, \"line_end\": \"crlf\"}"

mentdb
A1  A very lon

fixed write <path> <json_rows> <json_layout>

Description

Write rows to a fixed width file (the directories are created)

Parameters

path: The file path - String - required
json_rows: The rows - String - required
json_layout: The layout - String - required

admin
-> "[layout]" "[{\"name\": \"code\", \"length\": 5}, {\"name\": \"qty\", \"length\": 4, \"type\": \"int\"}]";
fixed write "tmp/tuto_etl/out.txt" "[{\"code\": \"A0001\", \"qty\": 12}, {\"code\": \"A0002\", \"qty\": 7}]" [layout];
-> "[res]" (file load "tmp/tuto_etl/out.txt");
file delete "tmp/tuto_etl/out.txt";
[res]

mentdb
A00010012
A00020007

fixed write <path> <json_rows> <json_layout> <json_params>

Description

Write a fixed width file with parameters

Parameters

path: The file path - String - required
json_rows: The rows - String - required
json_layout: The layout - String - required
json_params: The parameters - String - required

admin
-> "[layout]" "[{\"name\": \"account\", \"length\": 8}, {\"name\": \"label\", \"length\": 12}, {\"name\": \"amount\", \"length\": 10, \"type\": \"decimal\", \"decimals\": 2, \"sign\": \"trailing\"}, {\"name\": \"date\", \"length\": 8, \"type\": \"date\"}]";
-> "[rows]" "[{\"account\": \"41100001\", \"label\": \"Dupont SA\", \"amount\": -1250.5, \"date\": \"2026-10-31\"}, {\"account\": \"41100002\", \"label\": \"Martin\", \"amount\": 899, \"date\": \"2026-11-02\"}]";
fixed write "tmp/tuto_etl/bank.txt" [rows] [layout] "{\"encoding\": \"windows-1252\", \"line_end\": \"crlf\"}";
-> "[back]" (fixed read "tmp/tuto_etl/bank.txt" [layout] "{\"encoding\": \"windows-1252\"}");
file delete "tmp/tuto_etl/bank.txt";
[back]

mentdb
[{"account": "41100001", "label": "Dupont SA", "amount": -1250.5, "date": "2026-10-31"}, {"account": "41100002", "label": "Martin", "amount": 899, "date": "2026-11-02"}]