| Index: third_party/sqlite/sqlite-src-3100200/ext/rbu/sqlite3rbu.h
|
| diff --git a/third_party/sqlite/sqlite-src-3100200/ext/rbu/sqlite3rbu.h b/third_party/sqlite/sqlite-src-3100200/ext/rbu/sqlite3rbu.h
|
| deleted file mode 100644
|
| index f1a0f3cd845ed3858882b069299c956b9167fa7b..0000000000000000000000000000000000000000
|
| --- a/third_party/sqlite/sqlite-src-3100200/ext/rbu/sqlite3rbu.h
|
| +++ /dev/null
|
| @@ -1,461 +0,0 @@
|
| -/*
|
| -** 2014 August 30
|
| -**
|
| -** The author disclaims copyright to this source code. In place of
|
| -** a legal notice, here is a blessing:
|
| -**
|
| -** May you do good and not evil.
|
| -** May you find forgiveness for yourself and forgive others.
|
| -** May you share freely, never taking more than you give.
|
| -**
|
| -*************************************************************************
|
| -**
|
| -** This file contains the public interface for the RBU extension.
|
| -*/
|
| -
|
| -/*
|
| -** SUMMARY
|
| -**
|
| -** Writing a transaction containing a large number of operations on
|
| -** b-tree indexes that are collectively larger than the available cache
|
| -** memory can be very inefficient.
|
| -**
|
| -** The problem is that in order to update a b-tree, the leaf page (at least)
|
| -** containing the entry being inserted or deleted must be modified. If the
|
| -** working set of leaves is larger than the available cache memory, then a
|
| -** single leaf that is modified more than once as part of the transaction
|
| -** may be loaded from or written to the persistent media multiple times.
|
| -** Additionally, because the index updates are likely to be applied in
|
| -** random order, access to pages within the database is also likely to be in
|
| -** random order, which is itself quite inefficient.
|
| -**
|
| -** One way to improve the situation is to sort the operations on each index
|
| -** by index key before applying them to the b-tree. This leads to an IO
|
| -** pattern that resembles a single linear scan through the index b-tree,
|
| -** and all but guarantees each modified leaf page is loaded and stored
|
| -** exactly once. SQLite uses this trick to improve the performance of
|
| -** CREATE INDEX commands. This extension allows it to be used to improve
|
| -** the performance of large transactions on existing databases.
|
| -**
|
| -** Additionally, this extension allows the work involved in writing the
|
| -** large transaction to be broken down into sub-transactions performed
|
| -** sequentially by separate processes. This is useful if the system cannot
|
| -** guarantee that a single update process will run for long enough to apply
|
| -** the entire update, for example because the update is being applied on a
|
| -** mobile device that is frequently rebooted. Even after the writer process
|
| -** has committed one or more sub-transactions, other database clients continue
|
| -** to read from the original database snapshot. In other words, partially
|
| -** applied transactions are not visible to other clients.
|
| -**
|
| -** "RBU" stands for "Resumable Bulk Update". As in a large database update
|
| -** transmitted via a wireless network to a mobile device. A transaction
|
| -** applied using this extension is hence refered to as an "RBU update".
|
| -**
|
| -**
|
| -** LIMITATIONS
|
| -**
|
| -** An "RBU update" transaction is subject to the following limitations:
|
| -**
|
| -** * The transaction must consist of INSERT, UPDATE and DELETE operations
|
| -** only.
|
| -**
|
| -** * INSERT statements may not use any default values.
|
| -**
|
| -** * UPDATE and DELETE statements must identify their target rows by
|
| -** non-NULL PRIMARY KEY values. Rows with NULL values stored in PRIMARY
|
| -** KEY fields may not be updated or deleted. If the table being written
|
| -** has no PRIMARY KEY, affected rows must be identified by rowid.
|
| -**
|
| -** * UPDATE statements may not modify PRIMARY KEY columns.
|
| -**
|
| -** * No triggers will be fired.
|
| -**
|
| -** * No foreign key violations are detected or reported.
|
| -**
|
| -** * CHECK constraints are not enforced.
|
| -**
|
| -** * No constraint handling mode except for "OR ROLLBACK" is supported.
|
| -**
|
| -**
|
| -** PREPARATION
|
| -**
|
| -** An "RBU update" is stored as a separate SQLite database. A database
|
| -** containing an RBU update is an "RBU database". For each table in the
|
| -** target database to be updated, the RBU database should contain a table
|
| -** named "data_<target name>" containing the same set of columns as the
|
| -** target table, and one more - "rbu_control". The data_% table should
|
| -** have no PRIMARY KEY or UNIQUE constraints, but each column should have
|
| -** the same type as the corresponding column in the target database.
|
| -** The "rbu_control" column should have no type at all. For example, if
|
| -** the target database contains:
|
| -**
|
| -** CREATE TABLE t1(a INTEGER PRIMARY KEY, b TEXT, c UNIQUE);
|
| -**
|
| -** Then the RBU database should contain:
|
| -**
|
| -** CREATE TABLE data_t1(a INTEGER, b TEXT, c, rbu_control);
|
| -**
|
| -** The order of the columns in the data_% table does not matter.
|
| -**
|
| -** Instead of a regular table, the RBU database may also contain virtual
|
| -** tables or view named using the data_<target> naming scheme.
|
| -**
|
| -** Instead of the plain data_<target> naming scheme, RBU database tables
|
| -** may also be named data<integer>_<target>, where <integer> is any sequence
|
| -** of zero or more numeric characters (0-9). This can be significant because
|
| -** tables within the RBU database are always processed in order sorted by
|
| -** name. By judicious selection of the the <integer> portion of the names
|
| -** of the RBU tables the user can therefore control the order in which they
|
| -** are processed. This can be useful, for example, to ensure that "external
|
| -** content" FTS4 tables are updated before their underlying content tables.
|
| -**
|
| -** If the target database table is a virtual table or a table that has no
|
| -** PRIMARY KEY declaration, the data_% table must also contain a column
|
| -** named "rbu_rowid". This column is mapped to the tables implicit primary
|
| -** key column - "rowid". Virtual tables for which the "rowid" column does
|
| -** not function like a primary key value cannot be updated using RBU. For
|
| -** example, if the target db contains either of the following:
|
| -**
|
| -** CREATE VIRTUAL TABLE x1 USING fts3(a, b);
|
| -** CREATE TABLE x1(a, b)
|
| -**
|
| -** then the RBU database should contain:
|
| -**
|
| -** CREATE TABLE data_x1(a, b, rbu_rowid, rbu_control);
|
| -**
|
| -** All non-hidden columns (i.e. all columns matched by "SELECT *") of the
|
| -** target table must be present in the input table. For virtual tables,
|
| -** hidden columns are optional - they are updated by RBU if present in
|
| -** the input table, or not otherwise. For example, to write to an fts4
|
| -** table with a hidden languageid column such as:
|
| -**
|
| -** CREATE VIRTUAL TABLE ft1 USING fts4(a, b, languageid='langid');
|
| -**
|
| -** Either of the following input table schemas may be used:
|
| -**
|
| -** CREATE TABLE data_ft1(a, b, langid, rbu_rowid, rbu_control);
|
| -** CREATE TABLE data_ft1(a, b, rbu_rowid, rbu_control);
|
| -**
|
| -** For each row to INSERT into the target database as part of the RBU
|
| -** update, the corresponding data_% table should contain a single record
|
| -** with the "rbu_control" column set to contain integer value 0. The
|
| -** other columns should be set to the values that make up the new record
|
| -** to insert.
|
| -**
|
| -** If the target database table has an INTEGER PRIMARY KEY, it is not
|
| -** possible to insert a NULL value into the IPK column. Attempting to
|
| -** do so results in an SQLITE_MISMATCH error.
|
| -**
|
| -** For each row to DELETE from the target database as part of the RBU
|
| -** update, the corresponding data_% table should contain a single record
|
| -** with the "rbu_control" column set to contain integer value 1. The
|
| -** real primary key values of the row to delete should be stored in the
|
| -** corresponding columns of the data_% table. The values stored in the
|
| -** other columns are not used.
|
| -**
|
| -** For each row to UPDATE from the target database as part of the RBU
|
| -** update, the corresponding data_% table should contain a single record
|
| -** with the "rbu_control" column set to contain a value of type text.
|
| -** The real primary key values identifying the row to update should be
|
| -** stored in the corresponding columns of the data_% table row, as should
|
| -** the new values of all columns being update. The text value in the
|
| -** "rbu_control" column must contain the same number of characters as
|
| -** there are columns in the target database table, and must consist entirely
|
| -** of 'x' and '.' characters (or in some special cases 'd' - see below). For
|
| -** each column that is being updated, the corresponding character is set to
|
| -** 'x'. For those that remain as they are, the corresponding character of the
|
| -** rbu_control value should be set to '.'. For example, given the tables
|
| -** above, the update statement:
|
| -**
|
| -** UPDATE t1 SET c = 'usa' WHERE a = 4;
|
| -**
|
| -** is represented by the data_t1 row created by:
|
| -**
|
| -** INSERT INTO data_t1(a, b, c, rbu_control) VALUES(4, NULL, 'usa', '..x');
|
| -**
|
| -** Instead of an 'x' character, characters of the rbu_control value specified
|
| -** for UPDATEs may also be set to 'd'. In this case, instead of updating the
|
| -** target table with the value stored in the corresponding data_% column, the
|
| -** user-defined SQL function "rbu_delta()" is invoked and the result stored in
|
| -** the target table column. rbu_delta() is invoked with two arguments - the
|
| -** original value currently stored in the target table column and the
|
| -** value specified in the data_xxx table.
|
| -**
|
| -** For example, this row:
|
| -**
|
| -** INSERT INTO data_t1(a, b, c, rbu_control) VALUES(4, NULL, 'usa', '..d');
|
| -**
|
| -** is similar to an UPDATE statement such as:
|
| -**
|
| -** UPDATE t1 SET c = rbu_delta(c, 'usa') WHERE a = 4;
|
| -**
|
| -** Finally, if an 'f' character appears in place of a 'd' or 's' in an
|
| -** ota_control string, the contents of the data_xxx table column is assumed
|
| -** to be a "fossil delta" - a patch to be applied to a blob value in the
|
| -** format used by the fossil source-code management system. In this case
|
| -** the existing value within the target database table must be of type BLOB.
|
| -** It is replaced by the result of applying the specified fossil delta to
|
| -** itself.
|
| -**
|
| -** If the target database table is a virtual table or a table with no PRIMARY
|
| -** KEY, the rbu_control value should not include a character corresponding
|
| -** to the rbu_rowid value. For example, this:
|
| -**
|
| -** INSERT INTO data_ft1(a, b, rbu_rowid, rbu_control)
|
| -** VALUES(NULL, 'usa', 12, '.x');
|
| -**
|
| -** causes a result similar to:
|
| -**
|
| -** UPDATE ft1 SET b = 'usa' WHERE rowid = 12;
|
| -**
|
| -** The data_xxx tables themselves should have no PRIMARY KEY declarations.
|
| -** However, RBU is more efficient if reading the rows in from each data_xxx
|
| -** table in "rowid" order is roughly the same as reading them sorted by
|
| -** the PRIMARY KEY of the corresponding target database table. In other
|
| -** words, rows should be sorted using the destination table PRIMARY KEY
|
| -** fields before they are inserted into the data_xxx tables.
|
| -**
|
| -** USAGE
|
| -**
|
| -** The API declared below allows an application to apply an RBU update
|
| -** stored on disk to an existing target database. Essentially, the
|
| -** application:
|
| -**
|
| -** 1) Opens an RBU handle using the sqlite3rbu_open() function.
|
| -**
|
| -** 2) Registers any required virtual table modules with the database
|
| -** handle returned by sqlite3rbu_db(). Also, if required, register
|
| -** the rbu_delta() implementation.
|
| -**
|
| -** 3) Calls the sqlite3rbu_step() function one or more times on
|
| -** the new handle. Each call to sqlite3rbu_step() performs a single
|
| -** b-tree operation, so thousands of calls may be required to apply
|
| -** a complete update.
|
| -**
|
| -** 4) Calls sqlite3rbu_close() to close the RBU update handle. If
|
| -** sqlite3rbu_step() has been called enough times to completely
|
| -** apply the update to the target database, then the RBU database
|
| -** is marked as fully applied. Otherwise, the state of the RBU
|
| -** update application is saved in the RBU database for later
|
| -** resumption.
|
| -**
|
| -** See comments below for more detail on APIs.
|
| -**
|
| -** If an update is only partially applied to the target database by the
|
| -** time sqlite3rbu_close() is called, various state information is saved
|
| -** within the RBU database. This allows subsequent processes to automatically
|
| -** resume the RBU update from where it left off.
|
| -**
|
| -** To remove all RBU extension state information, returning an RBU database
|
| -** to its original contents, it is sufficient to drop all tables that begin
|
| -** with the prefix "rbu_"
|
| -**
|
| -** DATABASE LOCKING
|
| -**
|
| -** An RBU update may not be applied to a database in WAL mode. Attempting
|
| -** to do so is an error (SQLITE_ERROR).
|
| -**
|
| -** While an RBU handle is open, a SHARED lock may be held on the target
|
| -** database file. This means it is possible for other clients to read the
|
| -** database, but not to write it.
|
| -**
|
| -** If an RBU update is started and then suspended before it is completed,
|
| -** then an external client writes to the database, then attempting to resume
|
| -** the suspended RBU update is also an error (SQLITE_BUSY).
|
| -*/
|
| -
|
| -#ifndef _SQLITE3RBU_H
|
| -#define _SQLITE3RBU_H
|
| -
|
| -#include "sqlite3.h" /* Required for error code definitions */
|
| -
|
| -#ifdef __cplusplus
|
| -extern "C" {
|
| -#endif
|
| -
|
| -typedef struct sqlite3rbu sqlite3rbu;
|
| -
|
| -/*
|
| -** Open an RBU handle.
|
| -**
|
| -** Argument zTarget is the path to the target database. Argument zRbu is
|
| -** the path to the RBU database. Each call to this function must be matched
|
| -** by a call to sqlite3rbu_close(). When opening the databases, RBU passes
|
| -** the SQLITE_CONFIG_URI flag to sqlite3_open_v2(). So if either zTarget
|
| -** or zRbu begin with "file:", it will be interpreted as an SQLite
|
| -** database URI, not a regular file name.
|
| -**
|
| -** If the zState argument is passed a NULL value, the RBU extension stores
|
| -** the current state of the update (how many rows have been updated, which
|
| -** indexes are yet to be updated etc.) within the RBU database itself. This
|
| -** can be convenient, as it means that the RBU application does not need to
|
| -** organize removing a separate state file after the update is concluded.
|
| -** Or, if zState is non-NULL, it must be a path to a database file in which
|
| -** the RBU extension can store the state of the update.
|
| -**
|
| -** When resuming an RBU update, the zState argument must be passed the same
|
| -** value as when the RBU update was started.
|
| -**
|
| -** Once the RBU update is finished, the RBU extension does not
|
| -** automatically remove any zState database file, even if it created it.
|
| -**
|
| -** By default, RBU uses the default VFS to access the files on disk. To
|
| -** use a VFS other than the default, an SQLite "file:" URI containing a
|
| -** "vfs=..." option may be passed as the zTarget option.
|
| -**
|
| -** IMPORTANT NOTE FOR ZIPVFS USERS: The RBU extension works with all of
|
| -** SQLite's built-in VFSs, including the multiplexor VFS. However it does
|
| -** not work out of the box with zipvfs. Refer to the comment describing
|
| -** the zipvfs_create_vfs() API below for details on using RBU with zipvfs.
|
| -*/
|
| -sqlite3rbu *sqlite3rbu_open(
|
| - const char *zTarget,
|
| - const char *zRbu,
|
| - const char *zState
|
| -);
|
| -
|
| -/*
|
| -** Internally, each RBU connection uses a separate SQLite database
|
| -** connection to access the target and rbu update databases. This
|
| -** API allows the application direct access to these database handles.
|
| -**
|
| -** The first argument passed to this function must be a valid, open, RBU
|
| -** handle. The second argument should be passed zero to access the target
|
| -** database handle, or non-zero to access the rbu update database handle.
|
| -** Accessing the underlying database handles may be useful in the
|
| -** following scenarios:
|
| -**
|
| -** * If any target tables are virtual tables, it may be necessary to
|
| -** call sqlite3_create_module() on the target database handle to
|
| -** register the required virtual table implementations.
|
| -**
|
| -** * If the data_xxx tables in the RBU source database are virtual
|
| -** tables, the application may need to call sqlite3_create_module() on
|
| -** the rbu update db handle to any required virtual table
|
| -** implementations.
|
| -**
|
| -** * If the application uses the "rbu_delta()" feature described above,
|
| -** it must use sqlite3_create_function() or similar to register the
|
| -** rbu_delta() implementation with the target database handle.
|
| -**
|
| -** If an error has occurred, either while opening or stepping the RBU object,
|
| -** this function may return NULL. The error code and message may be collected
|
| -** when sqlite3rbu_close() is called.
|
| -**
|
| -** Database handles returned by this function remain valid until the next
|
| -** call to any sqlite3rbu_xxx() function other than sqlite3rbu_db().
|
| -*/
|
| -sqlite3 *sqlite3rbu_db(sqlite3rbu*, int bRbu);
|
| -
|
| -/*
|
| -** Do some work towards applying the RBU update to the target db.
|
| -**
|
| -** Return SQLITE_DONE if the update has been completely applied, or
|
| -** SQLITE_OK if no error occurs but there remains work to do to apply
|
| -** the RBU update. If an error does occur, some other error code is
|
| -** returned.
|
| -**
|
| -** Once a call to sqlite3rbu_step() has returned a value other than
|
| -** SQLITE_OK, all subsequent calls on the same RBU handle are no-ops
|
| -** that immediately return the same value.
|
| -*/
|
| -int sqlite3rbu_step(sqlite3rbu *pRbu);
|
| -
|
| -/*
|
| -** Force RBU to save its state to disk.
|
| -**
|
| -** If a power failure or application crash occurs during an update, following
|
| -** system recovery RBU may resume the update from the point at which the state
|
| -** was last saved. In other words, from the most recent successful call to
|
| -** sqlite3rbu_close() or this function.
|
| -**
|
| -** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
|
| -*/
|
| -int sqlite3rbu_savestate(sqlite3rbu *pRbu);
|
| -
|
| -/*
|
| -** Close an RBU handle.
|
| -**
|
| -** If the RBU update has been completely applied, mark the RBU database
|
| -** as fully applied. Otherwise, assuming no error has occurred, save the
|
| -** current state of the RBU update appliation to the RBU database.
|
| -**
|
| -** If an error has already occurred as part of an sqlite3rbu_step()
|
| -** or sqlite3rbu_open() call, or if one occurs within this function, an
|
| -** SQLite error code is returned. Additionally, *pzErrmsg may be set to
|
| -** point to a buffer containing a utf-8 formatted English language error
|
| -** message. It is the responsibility of the caller to eventually free any
|
| -** such buffer using sqlite3_free().
|
| -**
|
| -** Otherwise, if no error occurs, this function returns SQLITE_OK if the
|
| -** update has been partially applied, or SQLITE_DONE if it has been
|
| -** completely applied.
|
| -*/
|
| -int sqlite3rbu_close(sqlite3rbu *pRbu, char **pzErrmsg);
|
| -
|
| -/*
|
| -** Return the total number of key-value operations (inserts, deletes or
|
| -** updates) that have been performed on the target database since the
|
| -** current RBU update was started.
|
| -*/
|
| -sqlite3_int64 sqlite3rbu_progress(sqlite3rbu *pRbu);
|
| -
|
| -/*
|
| -** Create an RBU VFS named zName that accesses the underlying file-system
|
| -** via existing VFS zParent. Or, if the zParent parameter is passed NULL,
|
| -** then the new RBU VFS uses the default system VFS to access the file-system.
|
| -** The new object is registered as a non-default VFS with SQLite before
|
| -** returning.
|
| -**
|
| -** Part of the RBU implementation uses a custom VFS object. Usually, this
|
| -** object is created and deleted automatically by RBU.
|
| -**
|
| -** The exception is for applications that also use zipvfs. In this case,
|
| -** the custom VFS must be explicitly created by the user before the RBU
|
| -** handle is opened. The RBU VFS should be installed so that the zipvfs
|
| -** VFS uses the RBU VFS, which in turn uses any other VFS layers in use
|
| -** (for example multiplexor) to access the file-system. For example,
|
| -** to assemble an RBU enabled VFS stack that uses both zipvfs and
|
| -** multiplexor (error checking omitted):
|
| -**
|
| -** // Create a VFS named "multiplex" (not the default).
|
| -** sqlite3_multiplex_initialize(0, 0);
|
| -**
|
| -** // Create an rbu VFS named "rbu" that uses multiplexor. If the
|
| -** // second argument were replaced with NULL, the "rbu" VFS would
|
| -** // access the file-system via the system default VFS, bypassing the
|
| -** // multiplexor.
|
| -** sqlite3rbu_create_vfs("rbu", "multiplex");
|
| -**
|
| -** // Create a zipvfs VFS named "zipvfs" that uses rbu.
|
| -** zipvfs_create_vfs_v3("zipvfs", "rbu", 0, xCompressorAlgorithmDetector);
|
| -**
|
| -** // Make zipvfs the default VFS.
|
| -** sqlite3_vfs_register(sqlite3_vfs_find("zipvfs"), 1);
|
| -**
|
| -** Because the default VFS created above includes a RBU functionality, it
|
| -** may be used by RBU clients. Attempting to use RBU with a zipvfs VFS stack
|
| -** that does not include the RBU layer results in an error.
|
| -**
|
| -** The overhead of adding the "rbu" VFS to the system is negligible for
|
| -** non-RBU users. There is no harm in an application accessing the
|
| -** file-system via "rbu" all the time, even if it only uses RBU functionality
|
| -** occasionally.
|
| -*/
|
| -int sqlite3rbu_create_vfs(const char *zName, const char *zParent);
|
| -
|
| -/*
|
| -** Deregister and destroy an RBU vfs created by an earlier call to
|
| -** sqlite3rbu_create_vfs().
|
| -**
|
| -** VFS objects are not reference counted. If a VFS object is destroyed
|
| -** before all database handles that use it have been closed, the results
|
| -** are undefined.
|
| -*/
|
| -void sqlite3rbu_destroy_vfs(const char *zName);
|
| -
|
| -#ifdef __cplusplus
|
| -} /* end of the 'extern "C"' block */
|
| -#endif
|
| -
|
| -#endif /* _SQLITE3RBU_H */
|
|
|