Bigger-Than-RAM DB v1 [OK] [1010406]

!7

concept BigEntry {
  S globalID;
  long fileNr, headerStart, start, length;
}

p {
  dbIndexing(BigEntry, 'globalID);
  
  S s = "Hello world";
  BigEntry entry = db_newStringEntry(s);
  print("Stored as: " + renderConcept(entry));
  assertEqualsVerbose(s, db_getText(entry));
  print("OK");
}

static BigEntry db_newStringEntry(S text) {
  lock dbLock();
  long fileNr = fileNrToAppendTo();
  S globalID = aGlobalID();
  File file = db_file(fileNr);
  long length = fileSize(file);
  long l = lUtf8(text);
  S header = globalID + " " + l + "\n";
  long start = length + lUtf8(header);
  appendToTextFile(file, header + text + "\n");
  ret cnew(BigEntry, +globalID, +fileNr, headerStart := length, +start, length := l);
}

static long fileNrToAppendTo() {
  ret 1;
}

static File db_file(long nr) {
  ret getProgramFile("db." + nr);
}

static S db_getText(BigEntry entry) {
  File f = db_file(entry.fileNr);
  ret fromUtf8(loadBinaryFilePart(f, entry.start, entry.start+entry.length));
}

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Snippet ID:	#1010406
Snippet name:	Bigger-Than-RAM DB v1 [OK]
Eternal ID of this version:	#1010406/4
Text MD5:	0586623e50acbf1012ef5be8c52d8050
Transpilation MD5:	6bdccc3df973fd99b781a104cfe1e8d3
Author:	stefan
Category:	javax / gui
Type:	JavaX source code (desktop)
Public (visible to everyone):	Yes
Archived (hidden from active list):	No
Created/modified:	2017-09-15 18:35:53
Source code size:	1032 bytes / 42 lines
Pitched / IR pitched:	No / No
Views / Downloads:	421 / 851
Version history:	3 change(s)
Referenced in:	[show references]

< > BotCompany Repo | #1010406 // Bigger-Than-RAM DB v1 [OK]

JavaX source code (desktop) [tags: use-pretranspiled] - run with: x30.jar

1	!7
2
3	concept BigEntry {
4	S globalID;
5	long fileNr, headerStart, start, length;
6	}
7
8	p {
9	dbIndexing(BigEntry, 'globalID);
10
11	S s = "Hello world";
12	BigEntry entry = db_newStringEntry(s);
13	print("Stored as: " + renderConcept(entry));
14	assertEqualsVerbose(s, db_getText(entry));
15	print("OK");
16	}
17
18	static BigEntry db_newStringEntry(S text) {
19	lock dbLock();
20	long fileNr = fileNrToAppendTo();
21	S globalID = aGlobalID();
22	File file = db_file(fileNr);
23	long length = fileSize(file);
24	long l = lUtf8(text);
25	S header = globalID + " " + l + "\n";
26	long start = length + lUtf8(header);
27	appendToTextFile(file, header + text + "\n");
28	ret cnew(BigEntry, +globalID, +fileNr, headerStart := length, +start, length := l);
29	}
30
31	static long fileNrToAppendTo() {
32	ret 1;
33	}
34
35	static File db_file(long nr) {
36	ret getProgramFile("db." + nr);
37	}
38
39	static S db_getText(BigEntry entry) {
40	File f = db_file(entry.fileNr);
41	ret fromUtf8(loadBinaryFilePart(f, entry.start, entry.start+entry.length));
42	}