2. 日期/时间函数: 3. EXTRACT,date_part函数支持的field: 时间差 字段used_time与字段add_time的分钟间隔差 date_part('MINUTE',used_time::TIMESTAMP-add_time::TIMESTAMP)
NEW.manu_value; --return null because main table does not really contain data return NULL; END; $BODY$ LANGUAGE plpgsql VOLATILE COST 100; ALTER FUNCTION on_insert_base_table_machine2() OWNER TO postgres; 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18....
=$ pg_basebackup-i/var/tmp/backups/2024-01-08_173902-FULL/backup_manifest-Ft-D"/var/tmp/backups/$( date +%Y-%m-%d_%H%M%S-INCREMENTAL )"pg_basebackup:error:couldNOTinitiate base backup:ERROR:incremental backups cannot be taken unlessWALsummarizationISenabledpg_basebackup:removingDATAdirectory"...
但在很多情况下,它可能会导致严重的性能损失和拖累整体吞吐量。相当长一段时间,我试图对这种开销进行良好的评估,之前写过how the volume of data transmission as part of SQL execution, as well as the cursor location, affects the overall performance: https://www.percona.com/blog/impact-of-network-and-...
在PostgreSQL 中,如果你想根据某个字符(例如 _)分割字符串,并获取分割后的特定部分,你可以使用 split_part 函数。这个函数允许你指定分隔符和想要获取的子字符串的位置。 示例代码 sql -- 示例数据表 CREATE TABLE example_table ( id serial PRIMARY KEY, data text ); -- 插入示例数据 INSERT INTO example_...
drop database [if exists]+ 数据库的名称 创建表 CREATE TABLE DEPARTMENT( ID INT PRIMARY KEY NOT NULL, DEPT CHAR(50) NOT NULL, EMP_ID INT NOT NULL); 查看表的基本信息 \d +表名 删除表 drop table +表名 2.pgsql的模式 可以看成一个表的集合,包含视图、索引、据类型、函数和操作符等。
pgbench -M prepared -n -r -P 1 -f ./test.sql -h$PGDATA-c 32 -j 32 -T 600 2. 实时跟踪 pgbench压测的同时,实时观测。 su - root perf top -agv -F1000解释 perf top --help NAME perf-top - System profiling tool. SYNOPSIS
pgbench-M prepared -n -r -P1-f ./test.sql -h $PGDATA -c32-j32-T600 2. 实时跟踪 pgbench压测的同时,实时观测。 su - root perf top -agv -F1000解释 perf top--helpNAMEperf-top -Systemprofiling tool. SYNOPSIS perf top [-e <EVENT> |--event=EVENT] [<options>]DESCRIPTION ...
Osm2pgsql is an essential part of many services that take OSM data and create maps from it. It is also used in the Nominatim geocoder and numerous other applications processing OSM data. More about osm2pgsql: Features Project history Who is using osm2pgsql?Examples...
buct_composedata where paraid = '14112402C30000000401' and systemtime between ('2020-05-31 22:01:30') and ('2020-05-31 22:01:30'::timestamp + '1 sec') 1. 2. 3. 4. 5. 函数 返回类型 描述 例子 to_char(timestamp, text) text 把时间戳转换成字串 to_char(current_timestamp, ‘HH...