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Overview
Comment: | Add further tests and documentation for the sessions rebase feature. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | sessions-rebase |
Files: | files | file ages | folders |
SHA3-256: |
7475a363ebb272ae23c0796fe7587714 |
User & Date: | dan 2018-03-20 20:27:03.438 |
Context
2018-03-21
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17:29 | Fix rebasing of UPDATE changes against a set of remote changesets that feature both OMIT and REPLACE conflict resolution on different fields of the same row. (check-in: d8bc3fdb6b user: dan tags: sessions-rebase) | |
2018-03-20
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20:27 | Add further tests and documentation for the sessions rebase feature. (check-in: 7475a363eb user: dan tags: sessions-rebase) | |
2018-03-16
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18:02 | Fix a problem with handling rebasing UPDATE changes for REPLACE conflict resolution. (check-in: f7bf71f1d4 user: dan tags: sessions-rebase) | |
Changes
Changes to ext/session/session_common.tcl.
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165 166 167 168 169 170 171 | } proc changeset_to_list {c} { set list [list] sqlite3session_foreach elem $c { lappend list $elem } lsort $list } | > | 165 166 167 168 169 170 171 172 | } proc changeset_to_list {c} { set list [list] sqlite3session_foreach elem $c { lappend list $elem } lsort $list } |
Changes to ext/session/sessionfault2.test.
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15 16 17 18 19 20 21 22 23 24 25 26 27 28 | if {![info exists testdir]} { set testdir [file join [file dirname [info script]] .. .. test] } source [file join [file dirname [info script]] session_common.tcl] source $testdir/tester.tcl ifcapable !session {finish_test; return} set testprefix sessionfault2 do_execsql_test 1.0.0 { CREATE TABLE t1(a PRIMARY KEY, b UNIQUE); INSERT INTO t1 VALUES(1, 1); INSERT INTO t1 VALUES(2, 2); INSERT INTO t1 VALUES(3, 3); | > > | 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 | if {![info exists testdir]} { set testdir [file join [file dirname [info script]] .. .. test] } source [file join [file dirname [info script]] session_common.tcl] source $testdir/tester.tcl ifcapable !session {finish_test; return} set testprefix sessionfault2 if 1 { do_execsql_test 1.0.0 { CREATE TABLE t1(a PRIMARY KEY, b UNIQUE); INSERT INTO t1 VALUES(1, 1); INSERT INTO t1 VALUES(2, 2); INSERT INTO t1 VALUES(3, 3); |
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98 99 100 101 102 103 104 105 106 107 | faultsim_restore_and_reopen } -body { sqlite3changeset_apply db $::C xConflict } -test { faultsim_test_result {0 {}} {1 SQLITE_NOMEM} faultsim_integrity_check } finish_test | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 | faultsim_restore_and_reopen } -body { sqlite3changeset_apply db $::C xConflict } -test { faultsim_test_result {0 {}} {1 SQLITE_NOMEM} faultsim_integrity_check } #------------------------------------------------------------------------- # OOM when collecting and apply a changeset that uses sqlite_stat1. # reset_db forcedelete test.db2 sqlite3 db2 test.db2 do_common_sql { CREATE TABLE t1(a PRIMARY KEY, b UNIQUE, c); CREATE INDEX i1 ON t1(c); INSERT INTO t1 VALUES(1, 2, 3); INSERT INTO t1 VALUES(4, 5, 6); INSERT INTO t1 VALUES(7, 8, 9); CREATE TABLE t2(a, b, c); INSERT INTO t2 VALUES(1, 2, 3); INSERT INTO t2 VALUES(4, 5, 6); INSERT INTO t2 VALUES(7, 8, 9); ANALYZE; } faultsim_save_and_close db2 close do_faultsim_test 1.1 -faults oom-* -prep { catch {db2 close} catch {db close} faultsim_restore_and_reopen sqlite3 db2 test.db2 } -body { do_then_apply_sql { INSERT INTO sqlite_stat1 VALUES('x', 'y', 45); UPDATE sqlite_stat1 SET stat = 123 WHERE tbl='t1' AND idx='i1'; UPDATE sqlite_stat1 SET stat = 456 WHERE tbl='t2'; } } -test { faultsim_test_result {0 {}} {1 SQLITE_NOMEM} faultsim_integrity_check if {$testrc==0} { compare_db db db2 } } } #------------------------------------------------------------------------- # OOM when collecting and using a rebase changeset. # reset_db do_execsql_test 2.0 { CREATE TABLE t3(a, b, c, PRIMARY KEY(b, c)); CREATE TABLE t4(x PRIMARY KEY, y, z); INSERT INTO t3 VALUES(1, 2, 3); INSERT INTO t3 VALUES(4, 2, 5); INSERT INTO t3 VALUES(7, 2, 9); INSERT INTO t4 VALUES('a', 'b', 'c'); INSERT INTO t4 VALUES('d', 'e', 'f'); INSERT INTO t4 VALUES('g', 'h', 'i'); } faultsim_save_and_close proc xConflict {ret args} { return $ret } do_test 2.1 { faultsim_restore_and_reopen set C1 [changeset_from_sql { INSERT INTO t3 VALUES(10, 11, 12); UPDATE t4 SET y='j' WHERE x='g'; DELETE FROM t4 WHERE x='a'; }] faultsim_restore_and_reopen set C2 [changeset_from_sql { INSERT INTO t3 VALUES(1000, 11, 12); DELETE FROM t4 WHERE x='g'; }] faultsim_restore_and_reopen sqlite3changeset_apply db $C1 [list xConflict OMIT] faultsim_save_and_close } {} do_faultsim_test 2.2 -faults oom* -prep { catch {db2 close} catch {db close} faultsim_restore_and_reopen sqlite3 db2 test.db2 } -body { set rebase [sqlite3changeset_apply_v2 db $::C2 [list xConflict OMIT]] set {} {} } -test { faultsim_test_result {0 {}} {1 SQLITE_NOMEM} } do_faultsim_test 2.3 -faults oom* -prep { catch {db2 close} catch {db close} faultsim_restore_and_reopen sqlite3 db2 test.db2 } -body { set rebase [sqlite3changeset_apply_v2 db $::C2 [list xConflict REPLACE]] set {} {} } -test { faultsim_test_result {0 {}} {1 SQLITE_NOMEM} } do_faultsim_test 2.4 -faults oom* -prep { catch {db2 close} catch {db close} faultsim_restore_and_reopen set ::rebase [sqlite3changeset_apply_v2 db $::C2 [list xConflict REPLACE]] } -body { sqlite3rebaser_create R R configure $::rebase R rebase $::C1 set {} {} } -test { catch { R delete } faultsim_test_result {0 {}} {1 SQLITE_NOMEM} } do_faultsim_test 2.5 -faults oom* -prep { catch {db2 close} catch {db close} faultsim_restore_and_reopen set ::rebase [sqlite3changeset_apply_v2 db $::C2 [list xConflict OMIT]] } -body { sqlite3rebaser_create R R configure $::rebase R rebase $::C1 set {} {} } -test { catch { R delete } faultsim_test_result {0 {}} {1 SQLITE_NOMEM} } finish_test |
Changes to ext/session/sessionrebase.test.
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55 56 57 58 59 60 61 62 63 64 65 66 67 68 | set ::lConflict $conflict_handler set blob [sqlite3changeset_apply_v2 db $changeset xConflict] execsql ROLLBACK uplevel [list do_test $tn [list changeset_to_list $blob] [list {*}$res]] } do_execsql_test 1.0 { CREATE TABLE t1(a INTEGER PRIMARY KEY, b); INSERT INTO t1 VALUES(1, 'value A'); } do_apply_v2_test 1.1.1 { UPDATE t1 SET b = 'value B' WHERE a=1; | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 | set ::lConflict $conflict_handler set blob [sqlite3changeset_apply_v2 db $changeset xConflict] execsql ROLLBACK uplevel [list do_test $tn [list changeset_to_list $blob] [list {*}$res]] } set ::lConflict [list] proc xConflict {args} { set res [lindex $::lConflict 0] set ::lConflict [lrange $::lConflict 1 end] return $res } # Take a copy of database test.db in file test.db2. Execute $sql1 # against test.db and $sql2 against test.db2. Capture a changeset # for each. Then send the test.db2 changeset to test.db and apply # it with the conflict handlers in $conflict_handler. Patch the # test.db changeset and then execute it against test.db2. Test that # the two databases come out the same. # proc do_rebase_test {tn sql1 sql2 conflict_handler {testsql ""} {testres ""}} { for {set i 1} {$i <= 2} {incr i} { forcedelete test.db2 test.db2-journal test.db2-wal forcecopy test.db test.db2 sqlite3 db2 test.db2 db eval BEGIN sqlite3session S1 db main S1 attach * execsql $sql1 db set c1 [S1 changeset] S1 delete if {$i==1} { sqlite3session S2 db2 main S2 attach * execsql $sql2 db2 set c2 [S2 changeset] S2 delete } else { set c2 [list] foreach sql [split $sql2 ";"] { if {[string is space $sql]} continue sqlite3session S2 db2 main S2 attach * execsql $sql db2 lappend c2 [S2 changeset] S2 delete } } set ::lConflict $conflict_handler set rebase [list] if {$i==1} { lappend rebase [sqlite3changeset_apply_v2 db $c2 xConflict] } else { foreach c $c2 { lappend rebase [sqlite3changeset_apply_v2 db $c xConflict] } } #if {$tn=="2.1.4"} { puts [changeset_to_list $rebase] ; breakpoint } #puts [changeset_to_list [lindex $rebase 0]] ; breakpoint #puts [llength $rebase] if {$i==2 && $tn=="3.3.1"} breakpoint sqlite3rebaser_create R foreach r $rebase { puts [changeset_to_list $r] R configure $r } set c1r [R rebase $c1] R delete #if {$tn=="2.1.4"} { puts [changeset_to_list $c1r] } sqlite3changeset_apply_v2 db2 $c1r xConflictAbort uplevel [list do_test $tn.$i.1 [list compare_db db db2] {}] db2 close if {$testsql!=""} { uplevel [list do_execsql_test $tn.$i.2 $testsql $testres] } db eval ROLLBACK } } do_execsql_test 1.0 { CREATE TABLE t1(a INTEGER PRIMARY KEY, b); INSERT INTO t1 VALUES(1, 'value A'); } do_apply_v2_test 1.1.1 { UPDATE t1 SET b = 'value B' WHERE a=1; |
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137 138 139 140 141 142 143 | # 2.1.9 - 1i2i1r # proc xConflictAbort {args} { return "ABORT" } | < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < | | | | | | | | | | | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 | # 2.1.9 - 1i2i1r # proc xConflictAbort {args} { return "ABORT" } reset_db do_execsql_test 2.1.0 { CREATE TABLE t1 (a INTEGER PRIMARY KEY, b TEXT); INSERT INTO t1 VALUES(1, 'one'); INSERT INTO t1 VALUES(2, 'two'); INSERT INTO t1 VALUES(3, 'three'); } do_rebase_test 2.1.1 { UPDATE t1 SET b = 'two.1' WHERE a=2 } { UPDATE t1 SET b = 'two.2' WHERE a=2; } { OMIT } { SELECT * FROM t1 } {1 one 2 two.1 3 three} do_rebase_test 2.1.2 { UPDATE t1 SET b = 'two.1' WHERE a=2 } { UPDATE t1 SET b = 'two.2' WHERE a=2; } { REPLACE } { SELECT * FROM t1 } {1 one 2 two.2 3 three} do_rebase_test 2.1.3 { DELETE FROM t1 WHERE a=3 } { DELETE FROM t1 WHERE a=3; } { OMIT } { SELECT * FROM t1 } {1 one 2 two} do_rebase_test 2.1.4 { DELETE FROM t1 WHERE a=1 } { UPDATE t1 SET b='one.2' WHERE a=1 } { OMIT } { SELECT * FROM t1 } {2 two 3 three} #do_rebase_test 2.1.5 { # DELETE FROM t1 WHERE a=1; #} { # UPDATE t1 SET b='one.2' WHERE a=1 #} { # REPLACE #} { SELECT * FROM t1 } {2 two 3 three} do_rebase_test 2.1.6 { UPDATE t1 SET b='three.1' WHERE a=3 } { DELETE FROM t1 WHERE a=3; } { OMIT } { SELECT * FROM t1 } {1 one 2 two 3 three.1} do_rebase_test 2.1.7 { UPDATE t1 SET b='three.1' WHERE a=3 } { DELETE FROM t1 WHERE a=3; } { REPLACE } { SELECT * FROM t1 } {1 one 2 two} do_rebase_test 2.1.8 { INSERT INTO t1 VALUES(4, 'four.1') } { INSERT INTO t1 VALUES(4, 'four.2'); } { REPLACE } { SELECT * FROM t1 } {1 one 2 two 3 three 4 four.2} do_rebase_test 2.1.9 { INSERT INTO t1 VALUES(4, 'four.1') } { INSERT INTO t1 VALUES(4, 'four.2'); } { OMIT } { SELECT * FROM t1 } {1 one 2 two 3 three 4 four.1} do_execsql_test 2.2.0 { CREATE TABLE t2(x, y, z PRIMARY KEY); INSERT INTO t2 VALUES('i', 'a', 'A'); INSERT INTO t2 VALUES('ii', 'b', 'B'); INSERT INTO t2 VALUES('iii', 'c', 'C'); CREATE TABLE t3(a INTEGER PRIMARY KEY, b, c); INSERT INTO t3 VALUES(-1, 'z', 'Z'); INSERT INTO t3 VALUES(-2, 'y', 'Y'); } do_rebase_test 2.2.1 { UPDATE t2 SET x=1 WHERE z='A' } { UPDATE t2 SET y='one' WHERE z='A'; } { } { SELECT * FROM t2 WHERE z='A' } { 1 one A } do_rebase_test 2.2.2 { UPDATE t2 SET x=1, y='one' WHERE z='B' } { UPDATE t2 SET y='two' WHERE z='B'; } { REPLACE } { SELECT * FROM t2 WHERE z='B' } { 1 two B } do_rebase_test 2.2.3 { UPDATE t2 SET x=1, y='one' WHERE z='B' } { UPDATE t2 SET y='two' WHERE z='B'; } { OMIT } { SELECT * FROM t2 WHERE z='B' } { 1 one B } #------------------------------------------------------------------------- reset_db do_execsql_test 3.0 { CREATE TABLE t3(a, b, c, PRIMARY KEY(b, c)); CREATE TABLE abcdefghijkl(x PRIMARY KEY, y, z); INSERT INTO t3 VALUES(1, 2, 3); INSERT INTO t3 VALUES(4, 2, 5); INSERT INTO t3 VALUES(7, 2, 9); INSERT INTO abcdefghijkl VALUES('a', 'b', 'c'); INSERT INTO abcdefghijkl VALUES('d', 'e', 'f'); INSERT INTO abcdefghijkl VALUES('g', 'h', 'i'); } foreach {tn p} { 1 OMIT 2 REPLACE } { do_rebase_test 3.1.$tn { INSERT INTO t3 VALUES(1, 1, 1); UPDATE abcdefghijkl SET y=2; } { INSERT INTO t3 VALUES(4, 1, 1); DELETE FROM abcdefghijkl; } [list $p $p $p $p $p $p $p $p] do_rebase_test 3.2.$tn { INSERT INTO abcdefghijkl SELECT * FROM t3; UPDATE t3 SET b=b+1; } { INSERT INTO t3 VALUES(3, 3, 3); INSERT INTO abcdefghijkl SELECT * FROM t3; } [list $p $p $p $p $p $p $p $p] do_rebase_test 3.3.$tn { INSERT INTO abcdefghijkl VALUES(22, 23, 24); } { INSERT INTO abcdefghijkl VALUES(22, 25, 26); UPDATE abcdefghijkl SET y=400 WHERE x=22; } [list $p $p $p $p $p $p $p $p] } finish_test |
Changes to ext/session/sqlite3session.c.
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592 593 594 595 596 597 598 | int iCol; /* Used to iterate through table columns */ for(iCol=0; iCol<pTab->nCol; iCol++){ if( pTab->abPK[iCol] ){ int n1 = sessionSerialLen(a1); int n2 = sessionSerialLen(a2); | | | 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 | int iCol; /* Used to iterate through table columns */ for(iCol=0; iCol<pTab->nCol; iCol++){ if( pTab->abPK[iCol] ){ int n1 = sessionSerialLen(a1); int n2 = sessionSerialLen(a2); if( n1!=n2 || memcmp(a1, a2, n1) ){ return 0; } a1 += n1; a2 += n2; }else{ if( bLeftPkOnly==0 ) a1 += sessionSerialLen(a1); if( bRightPkOnly==0 ) a2 += sessionSerialLen(a2); |
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2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 | int nSql = -1; if( 0==sqlite3_stricmp("sqlite_stat1", zTab) ){ zSql = sqlite3_mprintf( "SELECT tbl, ?2, stat FROM %Q.sqlite_stat1 WHERE tbl IS ?1 AND " "idx IS (CASE WHEN ?2=X'' THEN NULL ELSE ?2 END)", zDb ); }else{ int i; const char *zSep = ""; SessionBuffer buf = {0, 0, 0}; sessionAppendStr(&buf, "SELECT * FROM ", &rc); sessionAppendIdent(&buf, zDb, &rc); | > | 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 | int nSql = -1; if( 0==sqlite3_stricmp("sqlite_stat1", zTab) ){ zSql = sqlite3_mprintf( "SELECT tbl, ?2, stat FROM %Q.sqlite_stat1 WHERE tbl IS ?1 AND " "idx IS (CASE WHEN ?2=X'' THEN NULL ELSE ?2 END)", zDb ); if( zSql==0 ) rc = SQLITE_NOMEM; }else{ int i; const char *zSep = ""; SessionBuffer buf = {0, 0, 0}; sessionAppendStr(&buf, "SELECT * FROM ", &rc); sessionAppendIdent(&buf, zDb, &rc); |
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4535 4536 4537 4538 4539 4540 4541 | memset(pNew, 0, sizeof(SessionChange)); pNew->op = op2; pNew->bIndirect = bIndirect; pNew->nRecord = nRec; pNew->aRecord = (u8*)&pNew[1]; memcpy(pNew->aRecord, aRec, nRec); }else if( bRebase){ | < > > > > > > | 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 | memset(pNew, 0, sizeof(SessionChange)); pNew->op = op2; pNew->bIndirect = bIndirect; pNew->nRecord = nRec; pNew->aRecord = (u8*)&pNew[1]; memcpy(pNew->aRecord, aRec, nRec); }else if( bRebase){ /* ** op1=INSERT/R, op2=INSERT/R -> ** op1=INSERT/R, op2=INSERT/O -> ** op1=INSERT/O, op2=INSERT/R -> ** op1=INSERT/O, op2=INSERT/O -> */ }else{ int op1 = pExist->op; /* ** op1=INSERT, op2=INSERT -> Unsupported. Discard op2. ** op1=INSERT, op2=UPDATE -> INSERT. ** op1=INSERT, op2=DELETE -> (none) |
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5165 5166 5167 5168 5169 5170 5171 | } if( bDone==0 ){ sessionAppendByte(&sOut, pIter->op, &rc); sessionAppendByte(&sOut, pIter->bIndirect, &rc); sessionAppendBlob(&sOut, aRec, nRec, &rc); } | < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < | 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 | } if( bDone==0 ){ sessionAppendByte(&sOut, pIter->op, &rc); sessionAppendByte(&sOut, pIter->bIndirect, &rc); sessionAppendBlob(&sOut, aRec, nRec, &rc); } if( rc==SQLITE_OK && xOutput && sOut.nBuf>SESSIONS_STRM_CHUNK_SIZE ){ rc = xOutput(pOut, sOut.aBuf, sOut.nBuf); sOut.nBuf = 0; } if( rc ) break; } |
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Changes to ext/session/sqlite3session.h.
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1215 1216 1217 1218 1219 1220 1221 | #define SQLITE_CHANGESET_OMIT 0 #define SQLITE_CHANGESET_REPLACE 1 #define SQLITE_CHANGESET_ABORT 2 /* ** CAPI3REF: Rebasing changesets ** | > > > > > > > > > > > > > > > > > > > > > > > > | | | | | | | > > > | 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 | #define SQLITE_CHANGESET_OMIT 0 #define SQLITE_CHANGESET_REPLACE 1 #define SQLITE_CHANGESET_ABORT 2 /* ** CAPI3REF: Rebasing changesets ** ** Suppose there is a site hosting a database in state S0. And that ** modifications are made that move that database to state S1 and a ** changeset recorded (the "local" changeset). Then, a changeset based ** on S0 is received from another site (the "remote" changeset) and ** applied to the database. The database is then in state ** (S1+"remote"), where the exact state depends on any conflict ** resolution decisions (OMIT or REPLACE) made while applying "remote". ** Rebasing a changeset is to update it to take those conflict ** resolution decisions into account, so that the same conflicts ** do not have to be resolved elsewhere in the network. ** ** For example, if both the local and remote changesets contain an ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": ** ** local: INSERT INTO t1 VALUES(1, 'v1'); ** remote: INSERT INTO t1 VALUES(1, 'v2'); ** ** and the conflict resolution is REPLACE, then the INSERT change is ** removed from the local changeset (it was overridden). Or, if the ** conflict resolution was "OMIT", then the local changeset is modified ** to instead contain: ** ** UPDATE t1 SET b = 'v2' WHERE a=1; ** ** Changes within the local changeset are rebased as follows: ** ** <dl> ** <dt>Local INSERT<dd> ** This may only conflict with a remote INSERT. If the conflict ** resolution was OMIT, then add an UPDATE change to the rebased ** changeset. Or, if the conflict resolution was REPLACE, add ** nothing to the rebased changeset. ** ** <dt>Local DELETE<dd> ** This may conflict with a remote UPDATE or DELETE. In both cases the ** only possible resolution is OMIT. If the remote operation was a ** DELETE, then add no change to the rebased changeset. If the remote ** operation was an UPDATE, then the old.* fields of change are updated ** to reflect the new.* values in the UPDATE. ** ** <dt>Local UPDATE<dd> ** This may conflict with a remote UPDATE or DELETE. If it conflicts ** with a DELETE, and the conflict resolution was OMIT, then the update ** is changed into an INSERT. Any undefined values in the new.* record ** from the update change are filled in using the old.* values from ** the conflicting DELETE. Or, if the conflict resolution was REPLACE, ** the UPDATE change is simply omitted from the rebased changeset. ** ** If conflict is with a remote UPDATE and the resolution is OMIT, then ** the old.* values are rebased using the new.* values in the remote ** change. Or, if the resolution is REPLACE, then the change is copied ** into the rebased changeset with updates to columns also updated by ** the conflicting UPDATE removed. If this means no columns would be ** updated, the change is omitted. ** </dl> ** ** A local change may be rebased against multiple remote changes ** simultaneously. */ typedef struct sqlite3_rebaser sqlite3_rebaser; /* Create a new rebaser object */ int sqlite3rebaser_create(sqlite3_rebaser **ppNew); /* Call this one or more times to configure a rebaser */ |
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