Sqlite3-pragma - Revision history

Pchero: /* application_id */

2016-10-20T09:26:19Z

application_id

← Older revision		Revision as of 09:26, 20 October 2016
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	== application_id ==		== application_id ==
	The application_id PRAGMA is used to query or set the 32-bit unsigned big-endian "Application ID" integer located at offset 68 into the database header. Applications that use SQLite as their application file-format should set the Application ID integer to a unique integer so that utilities such as file(1) can determine the specific file type rather than just reporting "SQLite3 Database". A list of assigned application IDs can be seen by consulting the magic.txt file in the SQLite source repository.
	<pre>		<pre>
	PRAGMA schema.application_id;		PRAGMA schema.application_id;
	PRAGMA schema.application_id = integer;		PRAGMA schema.application_id = integer;
	</pre>		</pre>
			The application_id PRAGMA is used to query or set the 32-bit unsigned big-endian "Application ID" integer located at offset 68 into the database header. Applications that use SQLite as their application file-format should set the Application ID integer to a unique integer so that utilities such as file(1) can determine the specific file type rather than just reporting "SQLite3 Database". A list of assigned application IDs can be seen by consulting the magic.txt file in the SQLite source repository.

			== auto_vacuum ==
			database 의 auto-vacuum option 을 질의/설정한다.
			<pre>
			PRAGMA schema.auto_vacuum;
			PRAGMA schema.auto_vacuum = 0 \| NONE \| 1 \| FULL \| 2 \| INCREMENTAL;
			</pre>
			sqlite3 컴파일시, SQLITE_DEFAULT_AUTOVACUUM 옵션을 따로 지정하지 않는 한, 기본 설정 값은 0 또는 "NONE"이다.

			기본적으로 sqlite3 에서 DELETE 명령을 한다고 해도, 데이터베이스 자체의 파일 사이즈의 크기는 줄어들지 않는다. 이는 단지 DELETE 된 항목을 사용하지 않을 뿐이다. 이를 확실히 지우기 위해서는 VACUUM 명령어를 사용해야 하는데, auto_vacuum pragma 는 auto-vacuum 기능을 설정할 수 있도록 한다.

	== table_info() ==		== table_info() ==

Pchero: /* table_info() */

2016-10-20T08:51:34Z

table_info()

← Older revision		Revision as of 08:51, 20 October 2016
Line 65:		Line 65:
	vdbe_debug		vdbe_debug
	vdbe_listing		vdbe_listing
			</pre>

			== application_id ==
			The application_id PRAGMA is used to query or set the 32-bit unsigned big-endian "Application ID" integer located at offset 68 into the database header. Applications that use SQLite as their application file-format should set the Application ID integer to a unique integer so that utilities such as file(1) can determine the specific file type rather than just reporting "SQLite3 Database". A list of assigned application IDs can be seen by consulting the magic.txt file in the SQLite source repository.
			<pre>
			PRAGMA schema.application_id;
			PRAGMA schema.application_id = integer;
	</pre>		</pre>

Pchero: /* WAL(Write Ahead to Log) */

2016-10-17T09:52:32Z

WAL(Write Ahead to Log)

← Older revision		Revision as of 09:52, 17 October 2016
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	=== WAL(Write Ahead to Log) ===		=== WAL(Write Ahead to Log) ===
			원문은 이곳<ref>https://www.sqlite.org/wal.html</ref>에서 확인할 수 있다.

			쓰기 요청이 들어오면, 변경 사항을 먼저 WAL-Log 에 기록한다. 그리고 WAL-Log 파일이 1000 Page(Default)가 넘게되면, 일괄 데이터에 반영한다.

	== Reference ==		== Reference ==

Pchero: /* WAL(Write Ahead to Log) */

2016-10-17T09:48:22Z

WAL(Write Ahead to Log)

← Older revision		Revision as of 09:48, 17 October 2016
Line 110:		Line 110:
	=== WAL(Write Ahead to Log) ===		=== WAL(Write Ahead to Log) ===

			== Reference ==
			<references/>

	[[category:sqlite3]]		[[category:sqlite3]]

Pchero: /* jounal_mode */

2016-10-17T09:47:54Z

jounal_mode

← Older revision		Revision as of 09:47, 17 October 2016
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	== jounal_mode ==		== jounal_mode ==
			Sqlite3 DB의 Journal mode 를 설정한다.

			Sqlite3 의 Journal mode 에 대한 자세한 설명은 이곳<ref>https://www.sqlite.org/atomiccommit.html</ref>을 참조하도록 한다.
			<pre>
			PRAGMA schema.journal_mode;
			PRAGMA schema.journal_mode = DELETE \| TRUNCATE \| PERSIST \| MEMORY \| WAL \| OFF
			</pre>

			* DELETE(default)
			: Rollback journal file 을 매번 Create/Delete 한다.

			* TRUNCATE
			: Rollback journal file 을 매번 Create/Delete 하지 않고, 파일 사이즈만을 0으로 설정 후 재활용 한다.

			* PERSIST
			: 저널링 파일을 지우지 않는다.

			* MEMORY
			: 저널링 파일을 메모리에서 유지한다. Sqlite3 를 사용하는 어플리케이션에서 장애시 데이터는 유실된다.

			* WAL
			: 쓰기 요청이 들어오면 변경사항을 먼저 WAL-log 에 기록한다. 이후 일괄적으로 데이터에 반영한다.

			* OFF
			: 데이터 파일에 직접 기록한다. 문제 발생시 데이터 복원이 불가하다.

			=== WAL(Write Ahead to Log) ===


	[[category:sqlite3]]		[[category:sqlite3]]

Pchero at 09:19, 17 October 2016

2016-10-17T09:19:21Z

@@ Line 66: / Line 66: @@
 vdbe_listing
 </pre>
 [[category:sqlite3]]

Pchero: Created page with "== Overvew == Sqlite3 pragma 내용 정리 == List == 전체 Pragma 목록

 application_id auto_vacuum automatic_index busy_timeout cache_size cache_spill case_sensitive..."

2016-10-17T09:18:16Z

Created page with "== Overvew == Sqlite3 pragma 내용 정리 == List == 전체 Pragma 목록 <pre> application_id auto_vacuum automatic_index busy_timeout cache_size cache_spill case_sensitive..."

New page

== Overvew ==
Sqlite3 pragma 내용 정리

== List ==
전체 Pragma 목록
<pre>
application_id
auto_vacuum
automatic_index
busy_timeout
cache_size
cache_spill
case_sensitive_like
cell_size_check
checkpoint_fullfsync
collation_list
compile_options
count_changes
data_store_directory
data_version
database_list
default_cache_size
defer_foreign_keys
empty_result_callbacks
encoding
foreign_key_check
foreign_key_list
foreign_keys
freelist_count
full_column_names
fullfsync
ignore_check_constraints
incremental_vacuum
index_info
index_list
index_xinfo
integrity_check
journal_mode
journal_size_limit
legacy_file_format
locking_mode
max_page_count
mmap_size
page_count
page_size
parser_trace
query_only
quick_check
read_uncommitted
recursive_triggers
reverse_unordered_selects
schema_version
secure_delete
short_column_names
shrink_memory
soft_heap_limit
stats
synchronous
table_info
temp_store
temp_store_directory
threads
user_version
vdbe_addoptrace
vdbe_debug
vdbe_listing
</pre>

[[category:sqlite3]]