Add sqlite_progress_handler() API for specifying an progress callback (CVS 1111)
FossilOrigin-Name: ddb364635a207658664ea92fc677cf16a143a938
This commit is contained in:
danielk1977
parent
4df92bbd44
commit
348bb5d6c8
25
manifest
25
manifest
@ -1,5 +1,5 @@
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C Update\sto\sthe\sdate\sfunctions.\s(CVS\s1110)
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D 2003-10-10T02:09:57
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C Add\ssqlite_progress_handler()\sAPI\sfor\sspecifying\san\sprogress\scallback\s(CVS\s1111)
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D 2003-10-18T09:37:26
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F Makefile.in ab585a91e34bc33928a1b6181fa2f6ebd4fb17e1
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F Makefile.linux-gcc b86a99c493a5bfb402d1d9178dcdc4bd4b32f906
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F README f1de682fbbd94899d50aca13d387d1b3fd3be2dd
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@ -35,7 +35,7 @@ F src/func.c fce558b4c1d895e81091d6d5e7d86a192fc8e84c
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F src/hash.c 058f077c1f36f266581aa16f907a3903abf64aa3
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F src/hash.h cd0433998bc1a3759d244e1637fe5a3c13b53bf8
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F src/insert.c dc200ae04a36bd36e575272a069e20c528b7fbdf
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F src/main.c ae92469674db9987de2848e373cd41a394621e32
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F src/main.c 9422005bb4411cc08c2986fde3278ac5b87068a0
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F src/md5.c fe4f9c9c6f71dfc26af8da63e4d04489b1430565
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F src/os.c 97df440bc71f65e22df5d3d920ce39551c0a5f5a
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F src/os.h 729395fefcca4b81ae056aa9ff67b72bb40dd9e0
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@ -48,10 +48,10 @@ F src/random.c 19e8e00fe0df32a742f115773f57651be327cabe
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F src/select.c d79ac60ba1595ff3c94b12892e87098329776482
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F src/shell.c c2ba26c850874964f5ec1ebf6c43406f28e44c4a
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F src/shell.tcl 27ecbd63dd88396ad16d81ab44f73e6c0ea9d20e
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F src/sqlite.h.in f8ae61546942e5a81df0ce3118048bec8dc87be4
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F src/sqliteInt.h 5f706313beafcc2da8102c807c35e18b2b0a3572
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F src/sqlite.h.in e6cfff01fafc8a82ce82cd8c932af421dc9adb54
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F src/sqliteInt.h 74dc7989c9f2b46b50485d0455a8ef8d4f178708
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F src/table.c 4301926464d88d2c2c7cd21c3360aa75bf068b95
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F src/tclsqlite.c ec9e5b796bf9ec1483927e986828a205d4a7422a
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F src/tclsqlite.c 3efac6b5861ac149c41251d4d4c420c94be5ba6a
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F src/test1.c f9d5816610f7ec4168ab7b098d5207a5708712b6
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F src/test2.c 5014337d8576b731cce5b5a14bec4f0daf432700
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F src/test3.c 30985ebdfaf3ee1462a9b0652d3efbdc8d9798f5
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@ -61,7 +61,7 @@ F src/trigger.c ce83e017b407d046e909d05373d7f8ee70f9f7f9
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F src/update.c 24260b4fda00c9726d27699a0561d53c0dccc397
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F src/util.c f16efa2d60bfd4e31ae06b07ed149557e828d294
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F src/vacuum.c e4724eade07e4cf8897060a8cf632dbd92408eeb
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F src/vdbe.c a9923a38a24ee86dd2e237c9f7e9d0116e329394
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F src/vdbe.c 0928a242ced0b5d26292f3949fdab26fa4dc327d
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F src/vdbe.h 3957844e46fea71fd030e78f6a3bd2f7e320fb43
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F src/vdbeInt.h 2824bf88895b901b3a8c9e44527c67530e1c0dcb
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F src/vdbeaux.c 31abb8e3e57866913360381947e267a51fed92c6
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@ -109,6 +109,7 @@ F test/null.test c14d0f4739f21e929b8115b72bf0c765b6bb1721
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F test/pager.test dd31da9bee94a82e2e87e58cf286cfe809f8fc5f
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F test/pragma.test e7cb7ffd765c9158868b0b7a3771d54a0d5f5072
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F test/printf.test 3ed02f1361402c0767492cd5cef4650e61df8308
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F test/progress.test 701b6115c2613128ececdfe1398a1bd0e1a4cfb3 x
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F test/quick.test c527bdb899b12a8cd8ceecce45f72922099f4095
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F test/quote.test 08f23385c685d3dc7914ec760d492cacea7f6e3d
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F test/rowid.test 1936d0d866a8105ab53cf6cb40a549b6664d06ce
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@ -153,7 +154,7 @@ F www/arch.fig d5f9752a4dbf242e9cfffffd3f5762b6c63b3bcf
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F www/arch.png 82ef36db1143828a7abc88b1e308a5f55d4336f4
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F www/arch.tcl 44b589fc01d6829d43447ab40588b00aec5b9734
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F www/audit.tcl 90e09d580f79c7efec0c7d6f447b7ec5c2dce5c0
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F www/c_interface.tcl acacd31d4441de900e09ee48b5ffdef0162d8dc3
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F www/c_interface.tcl 17d8bd9e7b4fbdca47c30c8b9bcb728c351d55c0
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F www/changes.tcl 1188dd0e79f9a8c48996ff44e4d9e81789bf1503
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F www/conflict.tcl 81dd21f9a679e60aae049e9dd8ab53d59570cda2
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F www/datatypes.tcl 0cb28565580554fa7e03e8fcb303e87ce57757ae
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@ -173,7 +174,7 @@ F www/speed.tcl 2f6b1155b99d39adb185f900456d1d592c4832b3
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F www/sqlite.tcl 3c83b08cf9f18aa2d69453ff441a36c40e431604
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F www/tclsqlite.tcl b9271d44dcf147a93c98f8ecf28c927307abd6da
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F www/vdbe.tcl 9b9095d4495f37697fd1935d10e14c6015e80aa1
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P 54aa0fb236d17b53b194a667d68c71007c8e7687
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R 78b719cb974e90d3bbfc839a1c83b68b
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U drh
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Z 6362f853c8fee8f874044b89744bb342
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P 06d4e88394217fb1390b069bad82d6ac71981f72
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R cde37f606921798e43de3b54f3499f6d
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U danielk1977
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Z a955533f397af1a9a7db7d26a39908ea
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@ -1 +1 @@
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06d4e88394217fb1390b069bad82d6ac71981f72
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ddb364635a207658664ea92fc677cf16a143a938
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27
src/main.c
27
src/main.c
@ -14,7 +14,7 @@
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** other files are for internal use by SQLite and should not be
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** accessed by users of the library.
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**
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** $Id: main.c,v 1.142 2003/09/06 22:18:08 drh Exp $
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** $Id: main.c,v 1.143 2003/10/18 09:37:26 danielk1977 Exp $
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*/
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#include "sqliteInt.h"
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#include "os.h"
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@ -826,6 +826,31 @@ void sqlite_busy_handler(
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db->pBusyArg = pArg;
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}
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#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
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/*
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** This routine sets the progress callback for an Sqlite database to the
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** given callback function with the given argument. The progress callback will
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** be invoked every nOps opcodes.
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*/
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void sqlite_progress_handler(
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sqlite *db,
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int nOps,
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int (*xProgress)(void*),
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void *pArg
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){
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if( nOps>0 ){
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db->xProgress = xProgress;
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db->nProgressOps = nOps;
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db->pProgressArg = pArg;
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}else{
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db->xProgress = 0;
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db->nProgressOps = 0;
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db->pProgressArg = 0;
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}
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}
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#endif
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/*
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** This routine installs a default busy handler that waits for the
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** specified number of milliseconds before returning 0.
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@ -12,7 +12,7 @@
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** This header file defines the interface that the SQLite library
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** presents to client programs.
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**
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** @(#) $Id: sqlite.h.in,v 1.52 2003/09/06 22:18:08 drh Exp $
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** @(#) $Id: sqlite.h.in,v 1.53 2003/10/18 09:37:26 danielk1977 Exp $
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*/
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#ifndef _SQLITE_H_
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#define _SQLITE_H_
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@ -729,6 +729,33 @@ int sqlite_reset(sqlite_vm*, char **pzErrMsg);
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*/
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int sqlite_bind(sqlite_vm*, int idx, const char *value, int len, int copy);
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/*
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** This routine configures a callback function - the progress callback - that
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** is invoked periodically during long running calls to sqlite_exec(),
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** sqlite_step() and sqlite_get_table(). An example use for this API is to keep
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** a GUI updated during a large query.
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**
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** The progress callback is invoked once for every N virtual machine opcodes,
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** where N is the second argument to this function. The progress callback
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** itself is identified by the third argument to this function. The fourth
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** argument to this function is a void pointer passed to the progress callback
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** function each time it is invoked.
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**
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** If a call to sqlite_exec(), sqlite_step() or sqlite_get_table() results
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** in less than N opcodes being executed, then the progress callback is not
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** invoked.
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**
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** Calling this routine overwrites any previously installed progress callback.
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** To remove the progress callback altogether, pass NULL as the third
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** argument to this function.
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**
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** If the progress callback returns a result other than 0, then the current
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** query is immediately terminated and any database changes rolled back. If the
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** query was part of a larger transaction, then the transaction is not rolled
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** back and remains active. The sqlite_exec() call returns SQLITE_ABORT.
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*/
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void sqlite_progress_handler(sqlite*, int, int(*)(void*), void*);
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#ifdef __cplusplus
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} /* End of the 'extern "C"' block */
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#endif
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@ -11,7 +11,7 @@
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*************************************************************************
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** Internal interface definitions for SQLite.
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**
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** @(#) $Id: sqliteInt.h,v 1.199 2003/09/27 13:39:39 drh Exp $
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** @(#) $Id: sqliteInt.h,v 1.200 2003/10/18 09:37:26 danielk1977 Exp $
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*/
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#include "config.h"
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#include "sqlite.h"
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@ -88,6 +88,7 @@
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/* #define SQLITE_OMIT_INMEMORYDB 1 */
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/* #define SQLITE_OMIT_VACUUM 1 */
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/* #define SQLITE_OMIT_TIMEDATE_FUNCS 1 */
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/* #define SQLITE_OMIT_PROGRESS_CALLBACK 1 */
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/*
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** Integers of known sizes. These typedefs might change for architectures
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@ -326,6 +327,11 @@ struct sqlite {
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/* Access authorization function */
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void *pAuthArg; /* 1st argument to the access auth function */
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#endif
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#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
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int (*xProgress)(void *); /* The progress callback */
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void *pProgressArg; /* Argument to the progress callback */
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int nProgressOps; /* Number of opcodes for progress callback */
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#endif
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};
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/*
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@ -11,7 +11,7 @@
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*************************************************************************
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** A TCL Interface to SQLite
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**
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** $Id: tclsqlite.c,v 1.50 2003/08/19 14:31:02 drh Exp $
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** $Id: tclsqlite.c,v 1.51 2003/10/18 09:37:26 danielk1977 Exp $
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*/
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#ifndef NO_TCL /* Omit this whole file if TCL is unavailable */
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@ -52,6 +52,7 @@ struct SqliteDb {
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Tcl_Interp *interp; /* The interpreter used for this database */
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char *zBusy; /* The busy callback routine */
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char *zTrace; /* The trace callback routine */
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char *zProgress; /* The progress callback routine */
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char *zAuth; /* The authorization callback routine */
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SqlFunc *pFunc; /* List of SQL functions */
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int rc; /* Return code of most recent sqlite_exec() */
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@ -325,6 +326,21 @@ static int DbBusyHandler(void *cd, const char *zTable, int nTries){
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return 1;
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}
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/*
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** This routine is invoked as the 'progress callback' for the database.
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*/
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static int DbProgressHandler(void *cd){
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SqliteDb *pDb = (SqliteDb*)cd;
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int rc;
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assert( pDb->zProgress );
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rc = Tcl_Eval(pDb->interp, pDb->zProgress);
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if( rc!=TCL_OK || atoi(Tcl_GetStringResult(pDb->interp)) ){
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return 1;
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}
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return 0;
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}
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/*
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** This routine is called by the SQLite trace handler whenever a new
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** block of SQL is executed. The TCL script in pDb->zTrace is executed.
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@ -457,13 +473,14 @@ static int DbObjCmd(void *cd, Tcl_Interp *interp, int objc,Tcl_Obj *const*objv){
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"close", "complete", "errorcode",
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"eval", "function", "last_insert_rowid",
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"onecolumn", "timeout", "trace",
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0
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"progress", 0
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};
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enum DB_enum {
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DB_AUTHORIZER, DB_BUSY, DB_CHANGES,
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DB_CLOSE, DB_COMPLETE, DB_ERRORCODE,
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DB_EVAL, DB_FUNCTION, DB_LAST_INSERT_ROWID,
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DB_ONECOLUMN, DB_TIMEOUT, DB_TRACE,
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DB_PROGRESS,
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};
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if( objc<2 ){
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@ -562,6 +579,48 @@ static int DbObjCmd(void *cd, Tcl_Interp *interp, int objc,Tcl_Obj *const*objv){
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break;
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}
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/* $db progress ?N CALLBACK?
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**
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** Invoke the given callback every N virtual machine opcodes while executing
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** queries.
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*/
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case DB_PROGRESS: {
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if( objc==2 ){
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if( pDb->zProgress ){
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Tcl_AppendResult(interp, pDb->zProgress, 0);
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}
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}else if( objc==4 ){
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char *zProgress;
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int len;
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int N;
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if( TCL_OK!=Tcl_GetIntFromObj(interp, objv[2], &N) ){
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return TCL_ERROR;
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};
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if( pDb->zProgress ){
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Tcl_Free(pDb->zProgress);
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}
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zProgress = Tcl_GetStringFromObj(objv[3], &len);
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if( zProgress && len>0 ){
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pDb->zProgress = Tcl_Alloc( len + 1 );
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strcpy(pDb->zProgress, zProgress);
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}else{
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pDb->zProgress = 0;
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}
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#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
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if( pDb->zProgress ){
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pDb->interp = interp;
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sqlite_progress_handler(pDb->db, N, DbProgressHandler, pDb);
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}else{
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sqlite_progress_handler(pDb->db, 0, 0, 0);
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}
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#endif
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}else{
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Tcl_WrongNumArgs(interp, 2, objv, "N CALLBACK");
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return TCL_ERROR;
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}
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break;
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}
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/*
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** $db changes
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**
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22
src/vdbe.c
22
src/vdbe.c
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** in this file for details. If in doubt, do not deviate from existing
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** commenting and indentation practices when changing or adding code.
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**
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** $Id: vdbe.c,v 1.241 2003/09/27 00:56:32 drh Exp $
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** $Id: vdbe.c,v 1.242 2003/10/18 09:37:26 danielk1977 Exp $
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*/
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#include "sqliteInt.h"
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#include "os.h"
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@ -529,6 +529,9 @@ int sqliteVdbeExec(
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unsigned long long start; /* CPU clock count at start of opcode */
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int origPc; /* Program counter at start of opcode */
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#endif
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#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
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int nProgressOps = 0; /* Opcodes executed since progress callback. */
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#endif
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if( p->magic!=VDBE_MAGIC_RUN ) return SQLITE_MISUSE;
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assert( db->magic==SQLITE_MAGIC_BUSY );
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@ -556,6 +559,23 @@ int sqliteVdbeExec(
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}
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#endif
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#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
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/* Call the progress callback if it is configured and the required number
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** of VDBE ops have been executed (either since this invocation of
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** sqliteVdbeExec() or since last time the progress callback was called).
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** If the progress callback returns non-zero, exit the virtual machine with
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** a return code SQLITE_ABORT.
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*/
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if( db->xProgress && (db->nProgressOps==nProgressOps) ){
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if( db->xProgress(db->pProgressArg)!=0 ){
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rc = SQLITE_ABORT;
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continue; /* skip to the next iteration of the for loop */
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}
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nProgressOps = 0;
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}
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nProgressOps++;
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#endif
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switch( pOp->opcode ){
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/*****************************************************************************
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118
test/progress.test
Executable file
118
test/progress.test
Executable file
@ -0,0 +1,118 @@
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# 2001 September 15
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#
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# The author disclaims copyright to this source code. In place of
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# a legal notice, here is a blessing:
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#
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# May you do good and not evil.
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# May you find forgiveness for yourself and forgive others.
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# May you share freely, never taking more than you give.
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#
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#***********************************************************************
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# This file implements regression tests for SQLite library. The
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# focus of this file is testing the 'progress callback'.
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#
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# $Id: progress.test,v 1.1 2003/10/18 09:37:27 danielk1977 Exp $
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set testdir [file dirname $argv0]
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source $testdir/tester.tcl
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# Build some test data
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#
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execsql {
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BEGIN;
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CREATE TABLE t1(a);
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INSERT INTO t1 VALUES(1);
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INSERT INTO t1 VALUES(2);
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INSERT INTO t1 VALUES(3);
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INSERT INTO t1 VALUES(4);
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INSERT INTO t1 VALUES(5);
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INSERT INTO t1 VALUES(6);
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INSERT INTO t1 VALUES(7);
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INSERT INTO t1 VALUES(8);
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INSERT INTO t1 VALUES(9);
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INSERT INTO t1 VALUES(10);
|
||||
COMMIT;
|
||||
}
|
||||
|
||||
|
||||
# Test that the progress callback is invoked.
|
||||
do_test progress-1.0 {
|
||||
set counter 0
|
||||
db progress 1 "[namespace code {incr counter}] ; expr 0"
|
||||
execsql {
|
||||
SELECT * FROM t1
|
||||
}
|
||||
expr $counter > 1
|
||||
} 1
|
||||
|
||||
# Test that the query is abandoned when the progress callback returns non-zero
|
||||
do_test progress1.1 {
|
||||
set counter 0
|
||||
db progress 1 "[namespace code {incr counter}] ; expr 1"
|
||||
execsql {
|
||||
SELECT * FROM t1
|
||||
}
|
||||
set counter
|
||||
} 1
|
||||
|
||||
# Test that the query is rolled back when the progress callback returns
|
||||
# non-zero.
|
||||
do_test progress1.2 {
|
||||
|
||||
# This figures out how many opcodes it takes to copy 5 extra rows into t1.
|
||||
db progress 1 "[namespace code {incr five_rows}] ; expr 0"
|
||||
set five_rows 0
|
||||
execsql {
|
||||
INSERT INTO t1 SELECT a+10 FROM t1 WHERE a < 6
|
||||
}
|
||||
db progress 0 ""
|
||||
execsql {
|
||||
DELETE FROM t1 WHERE a > 10
|
||||
}
|
||||
|
||||
# Now set up the progress callback to abandon the query after the number of
|
||||
# opcodes to copy 5 rows. That way, when we try to copy 6 rows, we know
|
||||
# some data will have been inserted into the table by the time the progress
|
||||
# callback abandons the query.
|
||||
db progress $five_rows "expr 1"
|
||||
execsql {
|
||||
INSERT INTO t1 SELECT a+10 FROM t1 WHERE a < 7
|
||||
}
|
||||
execsql {
|
||||
SELECT count(*) FROM t1
|
||||
}
|
||||
} 10
|
||||
|
||||
# Test that an active transaction remains active and not rolled back after the
|
||||
# progress query abandons a query.
|
||||
do_test progress1.3 {
|
||||
|
||||
db progress 0 ""
|
||||
execsql BEGIN
|
||||
execsql {
|
||||
INSERT INTO t1 VALUES(11)
|
||||
}
|
||||
db progress 1 "expr 1"
|
||||
execsql {
|
||||
INSERT INTO t1 VALUES(12)
|
||||
}
|
||||
db progress 0 ""
|
||||
execsql COMMIT
|
||||
execsql {
|
||||
SELECT count(*) FROM t1
|
||||
}
|
||||
} 11
|
||||
|
||||
# Check that a value of 0 for N means no progress callback
|
||||
do_test progress1.4 {
|
||||
set counter 0
|
||||
db progress 0 "[namespace code {incr counter}] ; expr 0"
|
||||
execsql {
|
||||
SELECT * FROM t1;
|
||||
}
|
||||
set counter
|
||||
} 0
|
||||
|
||||
db progress 0 ""
|
||||
|
||||
finish_test
|
||||
@ -1,7 +1,7 @@
|
||||
#
|
||||
# Run this Tcl script to generate the sqlite.html file.
|
||||
#
|
||||
set rcsid {$Id: c_interface.tcl,v 1.38 2003/07/08 23:42:25 drh Exp $}
|
||||
set rcsid {$Id: c_interface.tcl,v 1.39 2003/10/18 09:37:27 danielk1977 Exp $}
|
||||
|
||||
puts {<html>
|
||||
<head>
|
||||
@ -635,6 +635,8 @@ char *sqlite_vmprintf(const char *zFormat, va_list);
|
||||
|
||||
void sqlite_freemem(char*);
|
||||
|
||||
void sqlite_progress_handler(sqlite*, int, int (*)(void*), void*);
|
||||
|
||||
</pre></blockquote>
|
||||
|
||||
<p>All of the above definitions are included in the "sqlite.h"
|
||||
@ -979,6 +981,30 @@ routine. The string pointer that these routines return should be freed
|
||||
by passing it to <b>sqlite_freemem()</b>.
|
||||
</p>
|
||||
|
||||
<h3>3.10 Performing background jobs during large queries </h2>
|
||||
|
||||
<p>The <b>sqlite_progress_handler()</b> routine can be used to register a
|
||||
callback routine with an SQLite database to be invoked periodically during long
|
||||
running calls to <b>sqlite_exec()</b>, <b>sqlite_step()</b> and the various
|
||||
wrapper functions.
|
||||
</p>
|
||||
|
||||
<p>The callback is invoked every N virtual machine operations, where N is
|
||||
supplied as the second argument to <b>sqlite_progress_handler()</b>. The third
|
||||
and fourth arguments to <b>sqlite_progress_handler()</b> are a pointer to the
|
||||
routine to be invoked and a void pointer to be passed as the first argument to
|
||||
it.
|
||||
</p>
|
||||
|
||||
<p>The time taken to execute each virtual machine operation can vary based on
|
||||
many factors. A typical value for a 1 GHz PC is between half and three million
|
||||
per second but may be much higher or lower, depending on the query. As such it
|
||||
is difficult to schedule background operations based on virtual machine
|
||||
operations. Instead, it is recommended that a callback be scheduled relatively
|
||||
frequently (say every 1000 instructions) and external timer routines used to
|
||||
determine whether or not background jobs need to be run.
|
||||
</p>
|
||||
|
||||
<a name="cfunc">
|
||||
<h2>4.0 Adding New SQL Functions</h2>
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user