8> <COMMIT T1> Redo log(记录新值) (No-Steal / No-Force) 恢复时，从前往后，对提交的事务 的日志做redo操作。 日志 <COMMIT T1> Undo+Redo 恢复时，从前往后对提交事务做 redo操作，从后往前对未提交事务 做undo操作 。 日志 <COMMIT T1> 假设 A=8, B=10, C =12 T1: A → 10 T2: B → 8; C → 10 17 Buffer Pool and Log Buffer 2. A transaction is not considered to be committed until all of its log records(including its commit record) have been written to stable storage. 第一点：Steal policy。更新non-volatile storage中的页面时，必须记录undo

executeUpdate(sql); 快速上⼿ Greenplum数据仓库 UDW Copyright © 2012-2021 UCloud 优刻得 18/206 stmt.close(); c.commit(); c.close(); } catch (Exception e) { e.printStackTrace(); System.err.println(e.getClass().getName()+": UCloud 优刻得 26/206 ADDRESS CHAR(50), SALARY REAL);''') print "Table created successfully" conn.commit() conn.close() ⽰例3. 插⼊记录 insert.py #!/usr/bin/python import psycopg2 conn = psycopg2.connect(database="dev" INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \ VALUES (2, 'Allen', 25, 'Texas', 15000.00 )"); conn.commit() print "Records created successfully"; conn.close() ⽰例4. 查询 select.py #!/usr/bin/python 快速上⼿

Synopsis 1197 Description 1198 Parameters 1199 Notes 1200 Examples 1200 Compatibility 1201 COMMIT 1201 Synopsis 1201 Description 1202 Parameters 1202 Notes 1202 Examples 1202 Compatibility transaction management. The CREATE PROCEDURE command provides functionality to execute commands like COMMIT or ROLLBACK inside the procedural code. VMware Greenplum Streaming Server (GPSS) version 1.10.1 that is not enclosed in a transaction is treated as a single-statement transaction—the BEGIN and COMMIT are added implicitly. This is similar to autocommit in some database systems. When a transaction

ALTER VIEW 1072 ANALYZE 1072 BEGIN 1073 CHECKPOINT 1073 CLOSE 1073 CLUSTER 1073 COMMENT 1073 COMMIT 1074 COPY 1074 CREATE AGGREGATE 1075 CREATE CAST 1076 CREATE COLLATION 1076 CREATE CONVERSION Synopsis 1195 Description 1195 Parameters 1196 Notes 1197 Examples 1197 Compatibility 1198 COMMIT 1198 COMMIT 0 Synopsis 1198 Description 1198 Parameters 1198 Notes 1198 Examples 1198 Compatibility 13107 : Resolves an issue where disk space for a dropped relation was not freed on transaction commit; Greenplum Database now truncates the files. 13105 : Resolves a file descriptor leak on AO segment

ALTER VIEW 1320 ANALYZE 1320 BEGIN 1321 CHECKPOINT 1321 CLOSE 1321 CLUSTER 1321 COMMENT 1321 COMMIT 1322 COPY 1322 CREATE AGGREGATE 1322 CREATE CAST 1324 VMware Greenplum 6 Documentation VMware Synopsis 1445 Description 1446 Parameters 1446 Notes 1447 Examples 1447 Compatibility 1448 COMMIT 1448 Synopsis 1449 Description 1449 Parameters 1449 Notes 1449 Examples 1449 Compatibility commands to child tables during pg_restore, which must run in utility mode. n/a : Reverts a problematic commit that enclosed a check for interrupts (CFI) in a try-catch statement. (Resolved by PR-13568.) n/a

ALTER VIEW 1303 ANALYZE 1303 BEGIN 1303 CHECKPOINT 1304 CLOSE 1304 CLUSTER 1304 COMMENT 1304 COMMIT 1305 COPY 1305 CREATE AGGREGATE 1305 CREATE CAST 1306 CREATE COLLATION 1307 CREATE CONVERSION VMware Greenplum 6 Documentation VMware, Inc 69 Notes 1428 Examples 1428 Compatibility 1429 COMMIT 1429 Synopsis 1429 Description 1429 Parameters 1429 Notes 1429 Examples 1429 Compatibility commands to child tables during pg_restore, which must run in utility mode. n/a Reverts a problematic commit that enclosed a check for interrupts (CFI) in a try-catch statement. (Resolved by PR-13568.) n/a

ALTER VIEW 1288 ANALYZE 1288 BEGIN 1289 CHECKPOINT 1289 CLOSE 1289 CLUSTER 1289 COMMENT 1289 COMMIT 1290 COPY 1290 CREATE AGGREGATE 1290 CREATE CAST 1292 CREATE COLLATION 1292 CREATE CONVERSION Synopsis 1412 Description 1413 Parameters 1413 Notes 1414 Examples 1414 Compatibility 1415 COMMIT 1415 Synopsis 1416 Description 1416 Parameters 1416 Notes 1416 Examples 1416 Compatibility commands to child tables during pg_restore, which must run in utility mode. n/a : Reverts a problematic commit that enclosed a check for interrupts (CFI) in a try-catch statement. (Resolved by PR-13568.) n/a

ALTER VIEW 1063 ANALYZE 1063 BEGIN 1064 CHECKPOINT 1064 CLOSE 1064 CLUSTER 1064 COMMENT 1064 COMMIT 1065 COPY 1065 CREATE AGGREGATE 1066 CREATE CAST 1067 CREATE COLLATION 1067 CREATE CONVERSION Synopsis 1186 Description 1186 Parameters 1187 Notes 1188 Examples 1188 Compatibility 1189 COMMIT 1189 COMMIT 0 Synopsis 1189 Description 1189 Parameters 1189 Notes 1189 Examples 1189 Compatibility Resolved a problem that could cause a transaction to incorrectly use single-phase commit instead of two-phase commit. 275569338 - Query Dispatcher : Resolved a problem that could cause the error, ERROR:

ALTER VIEW 1263 ANALYZE 1263 BEGIN 1263 CHECKPOINT 1264 CLOSE 1264 CLUSTER 1264 COMMENT 1264 COMMIT 1265 COPY 1265 VMware Tanzu Greenplum 6 Documentation VMware, Inc 58 CREATE AGGREGATE 1265 CREATE Synopsis 1384 Description 1385 Parameters 1385 Notes 1386 Examples 1386 Compatibility 1387 COMMIT 1387 Synopsis 1387 Description 1387 Parameters 1388 Notes 1388 Examples 1388 Compatibility commands to child tables during pg_restore, which must run in utility mode. n/a Reverts a problematic commit that enclosed a check for interrupts (CFI) in a try-catch statement. (Resolved by PR-13568.) n/a

ALTER VIEW 1258 ANALYZE 1258 BEGIN 1259 CHECKPOINT 1259 CLOSE 1259 CLUSTER 1259 COMMENT 1259 COMMIT 1260 COPY 1260 CREATE AGGREGATE 1260 CREATE CAST 1262 CREATE COLLATION 1262 CREATE CONVERSION Synopsis 1380 Description 1380 Parameters 1381 Notes 1382 Examples 1382 Compatibility 1383 COMMIT 1383 Synopsis 1383 Description 1383 Parameters 1383 Notes 1383 Examples 1383 Compatibility commands to child tables during pg_restore, which must run in utility mode. n/a : Reverts a problematic commit that enclosed a check for interrupts (CFI) in a try-catch statement. (Resolved by PR-13568.) n/a