Monitoring Utilities 273 About Concurrency Control in Greenplum Database 274 Snapshots 275 Transaction ID Wraparound 276 Transaction Isolation Modes 276 Removing Dead Rows from Tables 278 Example of Managing timestamptz, interval, float MEDIAN (expression) Example: SELECT departmzent_id, MEDIAN(salary) FROM employees GROUP BY department_id; Can take a two-dimensional array as input. Treats such arrays as matrices Builds an arbitrary record from a JSON object. See Note 1. As with all functions returning record, the caller must explicitly define the structure of the record with an AS clause. select * from json_to_record(‘{“a”:1

Monitoring Utilities 244 About Concurrency Control in Greenplum Database 245 Snapshots 246 Transaction ID Wraparound 246 Transaction Isolation Modes 247 Removing Dead Rows from Tables 248 Example of Managing timestamptz, interval, float MEDIAN (expression) Example: SELECT departmzent_id, MEDIAN(salary) FROM employees GROUP BY department_id; Can take a two-dimensional array as input. Treats such arrays as matrices Builds an arbitrary record from a JSON object. See Note 1. As with all functions returning record, the caller must explicitly define the structure of the record with an AS clause. select * from json_to_record(‘{“a”:1

Monitoring Utilities 164 About Concurrency Control in Greenplum Database 165 Snapshots 166 Transaction ID Wraparound 167 Transaction Isolation Levels 168 Read Committed Isolation Level 169 Repeatable Read System Maintenance Tasks 946 Routine Vacuum and Analyze 947 Transaction ID Management 947 Recovering from a Transaction ID Limit Error 948 System Catalog Maintenance 948 Regular System Catalog Maintenance arbitrary record from a JSON object. See the Notes. As with all functions returning record, the caller must explicitly define the structure of the record with an AS clause. select * from json_to_record(‘{“a”:1

Routine System Maintenance Tasks 0 Routine Vacuum and Analyze 622 Transaction ID Management 622 Recovering from a Transaction ID Limit Error 623 System Catalog Maintenance 623 Regular System Catalog Maintenance Parameters 1546 OS Resource Parameters 1546 Cost-Based Vacuum Delay Parameters 1546 Transaction ID Management Parameters 1547 GPORCA Parameters 1547 Query Tuning Parameters 1547 Postgres Planner 18 Documentation VMware, Inc. 114 gp_server_version 1599 gp_server_version_num 1599 gp_session_id 1599 gp_set_proc_affinity 1599 gp_set_read_only 1600 gp_statistics_pullup_from_child_partition 1600

Routine System Maintenance Tasks 0 Routine Vacuum and Analyze 630 Transaction ID Management 631 Recovering from a Transaction ID Limit Error 632 System Catalog Maintenance 632 Regular System Catalog Maintenance Parameters 1555 OS Resource Parameters 1555 Cost-Based Vacuum Delay Parameters 1555 Transaction ID Management Parameters 1556 GPORCA Parameters 1556 Query Tuning Parameters 1556 Postgres Planner 1609 gp_segments_for_planner 1609 gp_server_version 1609 gp_server_version_num 1609 gp_session_id 1610 gp_set_proc_affinity 1610 gp_set_read_only 1610 gp_statistics_pullup_from_child_partition 1610

Routine System Maintenance Tasks 0 Routine Vacuum and Analyze 554 Transaction ID Management 554 Recovering from a Transaction ID Limit Error 555 System Catalog Maintenance 555 Regular System Catalog Maintenance Parameters 1481 OS Resource Parameters 1481 Cost-Based Vacuum Delay Parameters 1481 Transaction ID Management Parameters 1481 GPORCA Parameters 1481 Query Tuning Parameters 1482 Postgres Planner 1532 gp_segments_for_planner 1532 gp_server_version 1533 gp_server_version_num 1533 gp_session_id 1533 gp_set_proc_affinity 1533 gp_set_read_only 1534 gp_statistics_pullup_from_child_partition 1534

System Maintenance Tasks 621 Routine Vacuum and Analyze 622 Transaction ID Management 622 Recovering from a Transaction ID Limit Error 623 System Catalog Maintenance 623 Regular System Catalog Maintenance Parameters 1567 OS Resource Parameters 1567 Cost-Based Vacuum Delay Parameters 1567 Transaction ID Management Parameters 1568 GPORCA Parameters 1568 Query Tuning Parameters 1568 Postgres Planner 107 gp_segments_for_planner 1621 gp_server_version 1621 gp_server_version_num 1622 gp_session_id 1622 gp_set_proc_affinity 1622 gp_set_read_only 1622 gp_statistics_pullup_from_child_partition 1622

Monitoring Utilities 281 About Concurrency Control in Greenplum Database 282 Snapshots 283 Transaction ID Wraparound 284 Transaction Isolation Levels 285 Read Committed Isolation Level 286 VMware Greenplum System Maintenance Tasks 1143 Routine Vacuum and Analyze 1143 Transaction ID Management 1144 Recovering from a Transaction ID Limit Error 1145 System Catalog Maintenance 1145 Regular System Catalog Parameters 1840 OS Resource Parameters 1841 Cost-Based Vacuum Delay Parameters 1841 Transaction ID Management Parameters 1841 Other Parameters 1841 GPORCA Parameters 1841 Query Tuning Parameters

Monitoring Utilities 269 About Concurrency Control in Greenplum Database 270 Snapshots 271 Transaction ID Wraparound 272 Transaction Isolation Modes 273 Removing Dead Rows from Tables 274 Example of Managing System Maintenance Tasks 1104 Routine Vacuum and Analyze 1104 Transaction ID Management 1105 Recovering from a Transaction ID Limit Error 1105 System Catalog Maintenance 1106 Regular System Catalog Parameters 1773 OS Resource Parameters 1773 Cost-Based Vacuum Delay Parameters 1773 Transaction ID Management Parameters 1774 GPORCA Parameters 1774 Query Tuning Parameters 1775 Postgres Planner

Greenplum Database 300 Snapshots 301 VMware Greenplum 6 Documentation VMware, Inc. 14 Transaction ID Wraparound 302 Transaction Isolation Levels 303 Read Committed Isolation Level 304 Repeatable Read System Maintenance Tasks 1127 Routine Vacuum and Analyze 1127 Transaction ID Management 1128 Recovering from a Transaction ID Limit Error 1129 System Catalog Maintenance 1129 Regular System Catalog Parameters 1834 OS Resource Parameters 1834 Cost-Based Vacuum Delay Parameters 1834 Transaction ID Management Parameters 1835 Other Parameters 1835 VMware Greenplum 6 Documentation VMware, Inc. 105