NB-076
61 lines
2.2 KiB
Markdown
61 lines
2.2 KiB
Markdown
# 03-matching-N-1: N:1 Matching (N master records match one detail record)
|
|
|
|
## 电信业务场景
|
|
|
|
多线路→请求书汇集。读取多条电话线路记录(LINE)和请求地址文件(BILL-ADDR)，按地址进行N:1汇集。同一个地址的多条线路汇总到一张请求书。
|
|
|
|
## Description
|
|
|
|
Tests N:1 matching where multiple master records sharing the same key match
|
|
a single detail record. The program groups masters by key, finds the
|
|
corresponding detail, and writes one output record per master that has a match.
|
|
|
|
## Record Layout
|
|
|
|
| Field | Type | Length | Description |
|
|
|------------|-----------------|--------|---------------------------|
|
|
| STD-KEY | PIC X | 10 | Record key |
|
|
| STD-DATA-1 | PIC X | 20 | Description text |
|
|
| STD-DATA-2 | PIC 9 | 10 | Numeric data (display) |
|
|
| STD-DATA-3 | PIC S9(7)V99 | 05 | Numeric data (COMP-3) |
|
|
|
|
Total record length: 45 bytes.
|
|
|
|
## Files
|
|
|
|
| File | Purpose |
|
|
|-----------------------------|-----------------------------------|
|
|
| main-03-matching-N-1.cbl | Main COBOL program (fixed format) |
|
|
| data-gen.sh | Generate test data files |
|
|
| run.sh | Compile, run, verify |
|
|
| README.md | This file |
|
|
|
|
## Data
|
|
|
|
- **master.dat**: 3 records, all with key `KEY00001` (N=3 masters)
|
|
- **detail.dat**: 2 records — `KEY00001` (matches the 3 masters),
|
|
`KEY00002` (unmatched, not referenced)
|
|
|
|
## Matching Logic
|
|
|
|
1. Read masters by group (all records sharing the same key).
|
|
2. Advance the detail pointer to find a key matching the group.
|
|
3. If a match is found, write one output record per master in the group.
|
|
4. If no match is found, skip the entire master group.
|
|
5. Unmatched detail records are also skipped.
|
|
|
|
## Test
|
|
|
|
| Check | Expected |
|
|
|------------------------|------------------------|
|
|
| Output records | 3 (3 masters x 1 match) |
|
|
| Output file size | 135 bytes (3 x 45) |
|
|
| Unmatched master groups| 0 (all 3 have a match) |
|
|
|
|
## Usage
|
|
|
|
```bash
|
|
cd 03-matching-N-1
|
|
bash run.sh
|
|
```
|