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testing environment Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz 32G memory SSD harddisk. postgresql.conf max_connections = 256 shared_buffers = 3GB # min 128kB work_mem = 16MB # min 64kB maintenance_work_mem = 256MB # min 1MB wal_buffers = 4MB checkpoint_timeout = 1 ...

1. PG CopyManager use sample code: package test.simple; //You need to include postgres jdbc jar into your project lib import org.postgresql.copy.CopyManager; import org.postgresql.core.BaseConnection; import java.io.FileInputStream; import java.io.FileWriter; import java.sql.Connection; import java.sql.DriverManager; impor ...

In MySQL, if a column type is TIMESTAMP or DATETIME and on update current_timestamp is set, the value of the field is automatically updated to the current time as the update command updates the line record. This feature is very useful in application development, making it easy to record the last update time of each line. But this feature is not ...

The pg_stat_states module provides a way to track execution statistics for all SQL statements executed by a server. The module must be loaded by adding pg_stat_states to shared_preload_libraries of postgresql.conf because it requires additional shared memory. This means that adding or removing the module requires a server reboot ...

Label PostgreSQL, track_counts, statistics, pg_stat_reset background The statstic module of PostgreSQL database has some counters for counting the number of records inserted, updated and deleted in each table. From these views, you can see some of the counts counted by the counter: postgres=# \dv pg_stat* List of rel ...

https://github.com/digoal/blog/blob/master/201601/20160107_02.md author digoal date 2016-01-07 Label PostgreSQL , xfs , ext4 , cgroup , iops , iohang , writeback , ordered , xfs logdev background Under Linux, ext4 and xfs are file systems with journals. Before writing metadata, you must first write the journal of metadata. (journal is ...

Label PostgreSQL, HTAP, OLTP, OLAP, Scenario and Performance Testing background PostgreSQL is a database with a long history, which can be traced back to 1973. It was first awarded by the 2014 Computer Turing Prize winner and the originator of relational database. Michael_Stonebraker PostgreSQL has similar functions, performance, architectur ...

Label PostgreSQL, HTAP, OLTP, OLAP, Scenario and Performance Testing background PostgreSQL is a database with a long history, which can be traced back to 1973. It was first awarded by the 2014 Computer Turing Prize winner and the originator of relational database. Michael_Stonebraker PostgreSQL has similar functions, performance, architectur ...

Label PostgreSQL, HTAP, OLTP, OLAP, Scenario and Performance Testing background PostgreSQL is a database with a long history, which can be traced back to 1973. It was first awarded by the 2014 Computer Turing Prize winner and the originator of relational database. Michael_Stonebraker PostgreSQL has similar functions, performance, architectur ...

Label PostgreSQL , 10.0 , libpq , jdbc , failover , loadbalance , multi host , target_session_attrs background The word database should be familiar in the Internet. But how can master-backup switching and applications work together seamlessly? You may have such questions. 1. What type of QUERY is sent to the main library and what type of QUE ...