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Fig 9-02
- 1. database cluster WAL buffer WALsegments Last XLOG record shared buffer pool © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 2. database cluster WAL buffer WALsegments (1) CHECKPOINT REDO point checkpoint CHECKPOINT CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool Do checkpoint © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 3. TABLE_Adatabase cluster WAL buffer WALsegments (1) CHECKPOINT LSN_0 REDO point checkpoint CHECKPOINT CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool (2) BEGIN; INSERT INTO TABLE_A VALUES('A'); Issue the first INSERT statement © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 4. TABLE_Adatabase cluster WAL buffer WALsegments (1) CHECKPOINT LSN_0 TABLE_A LSN_0 REDO point checkpoint CHECKPOINT CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool (2) BEGIN; INSERT INTO TABLE_A VALUES('A'); Load the TABLE_A's page © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 5. TABLE_A A (2) BEGIN; INSERT INTO TABLE_AVALUES('A'); database cluster WAL buffer WAL segments (1) CHECKPOINT LSN_0 LSN_0 TABLE_A LSN_0 REDO point checkpoint CHECKPOINT CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool Insert a tuple © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 6. TABLE_A A (2) BEGIN; INSERT INTO TABLE_AVALUES('A'); database cluster WAL buffer WAL segments A (1) CHECKPOINT LSN_0 LSN_0 TABLE_A LSN_0 REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool Write the XLOG record of this tuple to the WAL buffer © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 7. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A (1) CHECKPOINT LSN_0 LSN_0 TABLE_A LSN_0 REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool Invoke a commit action © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 8. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A (1) CHECKPOINT LSN_0 LSN_0 TABLE_A LSN_0 COMMIT REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool Write the XLOG record of this commit action © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 9. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A A (1) CHECKPOINT LSN_1 LSN_0 LSN_0 TABLE_A LSN_0 COMMIT COMMIT REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool Write and flush the XLOG records to WAL segment © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 10. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A A (1) CHECKPOINT LSN_1 LSN_0 LSN_0 LSN_1 TABLE_A LSN_0 COMMIT COMMIT REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record shared buffer pool Update TABLE_A's pd_lsn from LSN_0 to LSN_1 © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 11. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A A (1) CHECKPOINT LSN_1 LSN_0 LSN_0 LSN_1 TABLE_A LSN_0 COMMIT COMMIT REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record B A (4) BEGIN; INSERT INTO TABLE_A VALUES('B'); B LSN_1 LSN_2 shared buffer pool Issue the second statement and write a XLOG record © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 12. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A A (1) CHECKPOINT LSN_1 LSN_0 LSN_0 LSN_1 TABLE_A LSN_0 COMMIT COMMIT REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record B A (4) (5) BEGIN; INSERT INTO TABLE_A VALUES('B'); COMMIT; B LSN_1 LSN_2 shared buffer pool Invoke a commit action © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 13. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A A (1) CHECKPOINT LSN_1 LSN_0 LSN_0 LSN_1 TABLE_A LSN_0 COMMIT COMMIT REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record B A (4) (5) BEGIN; INSERT INTO TABLE_A VALUES('B'); COMMIT; B LSN_1 COMMIT LSN_2 shared buffer pool Write the XLOG record of this commit action © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 14. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A A (1) CHECKPOINT LSN_1 LSN_0 LSN_0 LSN_1 TABLE_A LSN_0 COMMIT COMMIT REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record B A (4) (5) BEGIN; INSERT INTO TABLE_A VALUES('B'); COMMIT; B B LSN_2 LSN_1 COMMIT COMMIT LSN_2 shared buffer pool Write and flush XLOG records to the WAL segment © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html
- 15. TABLE_A A (2) (3) BEGIN; INSERT INTOTABLE_A VALUES('A'); COMMIT; database cluster WAL buffer WAL segments A A (1) CHECKPOINT LSN_1 LSN_0 LSN_0 LSN_1 TABLE_A LSN_0 COMMIT COMMIT REDO point checkpoint CHECKPOINT LSN_1 CHECKPOINT REDO point checkpoint Last XLOG record B A (4) (5) BEGIN; INSERT INTO TABLE_A VALUES('B'); COMMIT; B B LSN_2 LSN_1 LSN_2 COMMIT COMMIT LSN_2 shared buffer pool Update TABLE_A's pd_lsn from LSN_1 to LSN_2 © Copyright 2015 Suzuki Hironobu All Rights Reserved. See also http://www.interdb.jp/pg/pgsql09.html