本文介绍如何在使用SELECT语法时添加any条件。 只需要大于其中一个值即为真。 plaintext teledb select from teledbpg where id > any (select 1 union select 3); id nickname + 3 pg 4 2 TELEDB (3 rows)

本文为您介绍json应用的相关操作。 创建json 类型字段表 plaintext teledb create table tjson(id int,fjson json); CREATE TABLE 插入数据 plaintext teledb insert into tjson values(1,'{"col1":1,"col2":"teledb"}'); INSERT 0 1 teledb insert into tjson values(2,'{"col1":1,"col2":"teledb","col3":"pgxz"}'); INSERT 0 1 teledb select from tjson; id fjson + 1 {"col1":1,"col2":"teledb"} 2 {"col1":1,"col2":"teledb","col3":"pgxz"} (2 rows) 通过键获得json对象域 plaintext teledb select fjson >'col2' as col2 ,fjson > 'col3' as col3 from tjson; col2 col3 + "teledb" "teledb" "pgxz" (2 rows) 以文本形式获取对象值 plaintext teledb select fjson >>'col2' as col2 ,fjson >> 'col3' as col3 from tjson; col2 col3 + teledb teledb pgxz (2 rows) teledb select fjson >>'col2' as col2 ,fjson >> 'col3' as col3 from tjson where fjson >> 'col3' is not null; col2 col3 + teledb pgxz (1 row)

本文为您介绍如何管理视图，包括创建视图、删除视图和物化视图使用。 创建视图 plaintext teledb create view trangeview as select from trange; CREATE VIEW teledb select from trangeview; f1 f2 f3 ++ 1 20230822 11:06:16.9783 1 2 20230822 11:06:16.9783 50 2 20230822 11:06:16.9783 110 3 20230822 11:06:16.9783 100 (4 rows) 数据类型重定义。 plaintext teledb drop view trangeview; DROP VIEW teledb create view trangeview as select f1,f2::date from trange; CREATE VIEW teledb select from trangeview; f1 f2 + 1 20230822 3 20230822 2 20230822 2 20230822 (4 rows) 数据类型重定义，以及取别名。 plaintext teledb drop view trangeview; DROP VIEW teledb create view trangeview as select f1,f2::date as mydate from trange; CREATE VIEW teledb select from trangeview; f1 mydate + 1 20230822 2 20230822 2 20230822 3 20230822 (4 rows) TeleDB支持视图引用表或字段改名联动，不受影响。 plaintext teledb d+ trangeview View "teledb.trangeview" Column Type Collation Nullable Default Storage Description ++++++ f1 bigint plain mydate date plain View definition: SELECT trange.f1, trange.f2::date AS mydate FROM trange; teledb

本文介绍只查询某个DN数据的操作。 plaintext teledb execute direct on (dn01) 'select from teledbpg'; id nickname + 1 teledb 1 hello,pgxc 2 TELEDB (3 rows) teledb execute direct on (dn02) 'select from teledbpg'; id nickname + 3 pg 4 (2 rows)

本文介绍如何在使用SELECT语法时进行聚合函数并发计算。 plaintext teledb set maxparallelworkerspergather to 0; SET Time: 0.214 ms teledb select count(1) from tcount; count 20000000 (1 row) Time: 2700.569 ms (00:02.701) teledb set maxparallelworkerspergather to 2; SET Time: 0.269 ms teledb select count(1) from tcount; count 20000000 (1 row) Time: 1867.719 ms (00:01.868)

本文为您介绍实例主机手动创建了teledbx用户导致开通实例失败的问题原因和解决方案。 问题现象 创建实例开通失败。 原因分析 经过查看错误日志，发现其手动创建teledbx用户。由于在开通创建实例时，系统会自动创建teledbx用户，无需手动创建。 解决方案 1. 执行如下命令删除实例主机teledbx用户。 plaintext userdel teledbx 2. 在管控台中选择实例管理 > 工单管理 ，单击所创建实例行所在的操作列的重新施工即可。

本文为您介绍创建实例开通时，不能添加主机的问题现象、原因和解决方案。 问题现象 实例开通时，不能添加主机。 原因分析 DCP控制台不能纳管主机。9083端口未放通。 解决方案 添加安全组，放通端口，即可创建开通实例。

本文为您介绍提交工单显示主机cpu或者内存不足的问题现象、问题原因和解决方案。 问题现象 提交工单时提示主机资源不足。 原因分析 通过查看错误日志发现需要的主机资源远超主机本身规格，实例主机规格是（96C256G），内存不够。 但是统计发现实例主机使用的资源是192G，与dcp计算的相差甚大。 解决方案 调整配置库的cgroupcluster表数据，降低比例。 plaintext usedcp selectoversaleratefromcgroupcluster updatecgroupclustersetoversalerate200;

本文为您介绍创建的目录、文件权限不足的问题现象、问题原因和解决方案。 问题现象 手动执行如下命令，出现如下报错日志。 sshp 22 oConnectTimeout10oStrictHostKeyCheckingnoteledb@10.218.14.144sudoyumyinstalldos2unixexpectreadlinecreatereponettoolslsofuuid 经过排查发现目录文件权限不对，用户组不具备读写操作权限。 原因分析 执行umask命令，发现其设置的值与实际不相符，查找出位0027，实际上位022才对，导致用户创建的文件或者目录用户组权限不对。 解决方案 方式一： 1. 执行如下命令，给解压出的安装包赋予读写执行权限。 plaintext cd/app sudo chmod R 755 teledbxv2.8.6centos.x8664 sudo chown R teledb:teledb teledbxv2.8.6centos.x8664 sshp 22 oConnectTimeout10oStrictHostKeyCheckingnoteledb@10.218.14.144sudoyumy installdos2unixexpectreadlinecreatereponettoolslsofuuid 2. 重新install，当出现如下回显信息表示安装成功。 方式二： 您可以修改umask的值，您可执行chmod命令授权也可参考如下方式修改umask的值。 plaintext 1、临时修改umask的值 umask022 2、永久修改umask的值 vim/etc/profile if[ $UID gt199] &&["/usr/bin/idgn""/usr/bin/idun"];thenumask022 else umask022 fi vim/etc/bashrc if [ $UID gt199] &&["/usr/bin/idgn""/usr/bin/idun"];thenumask002 else umask022 fi source/etc/profile sourcevim/etc/bashrc 检查 umask

drop index tsexsexidx; DROP INDEX teledb create index tsexsexidx on tsex (sex) where sex '女'; CREATE INDEX teledb analyze tsex; ANALYZE teledb explain select from tsex where sex '男'; QUERY PLAN Remote Fast Query Execution (cost0.00..0.00 rows0 width0) Node/s: dn01, dn02 > Seq Scan on tsex (cost0.00..9966.58 rows500539 width8) Filter: (sex '男'::text) (4 rows) teledb explain select from tsex where sex '女'; QUERY PLAN Remote Fast Query Execution (cost0.00..0.00 rows0 width0) Node/s: dn01, dn02 > Index Scan using tsexsexidx on tsex (cost0.14..13.15 rows67 width8) (3 rows) teledb q [teledb@localhost bin]$ ./telesql p 22222 U teledb d teledb Password for user teledb: telesql (TeleDB V6) Type "help" for help. teledb di+ tsexsexidx List of relations Schema Name Type Owner Table Size Allocated Size Description +++++++ public tsexsexidx index teledb tsex 16 kB 16 kB (1 row)

本文为您介绍如何通过SELECT语法访问函数。 plaintext teledb select md5(random()::text); md5 ed5b356234979a63efc6c4f6537c4853 (1 row)

本文为您介绍jsonb应用的相关操作。 创建jsonb类型字段表 plaintext teledb create table tjsonb(id int,fjsonb jsonb); CREATE TABLE 插入数据 plaintext teledb insert into tjsonb values(1,'{"col1":1,"col2":"teledb"}'); INSERT 0 1 teledb insert into tjsonb values(2,'{"col1":1,"col2":"teledb","col3":"pgxz"}'); INSERT 0 1 teledb select from tjsonb; id fjsonb + 1 {"col1": 1, "col2": "teledb"} 2 {"col1": 1, "col2": "teledb", "col3": "pgxz"} (2 rows jsonb插入时会移除重复的键，如下所示。 plaintext teledb insert into tjsonb values(3,'{"col1":1,"col2":"teledb","col2":"pgxz"}'); INSERT 0 1 teledb select from tjsonb; id fjsonb + 1 {"col1": 1, "col2": "teledb"} 2 {"col1": 1, "col2": "teledb", "col3": "pgxz"} 3 {"col1": 1, "col2": "pgxz"} (3 rows) 更新数据 增加元素。 plaintext teledb update tjsonb set fjsonb fjsonb '{"col3":"pgxz"}'::jsonb where id1; UPDATE 1 teledb select from tjsonb; id fjsonb + 2 {"col1": 1, "col2": "teledb", "col3": "pgxz"} 1 {"col1": 1, "col2": "teledb", "col3": "pgxz"} 3 {"col1": 1, "col2": "pgxz"} (3 rows) 更新原来的元素。 plaintext teledb

本文为您介绍如何删除索引。 plaintext teledb drop index tmulidxidx; DROP INDEX

alter table t owner to user1; ALTER TABLE teledb dt t List of relations Schema Name Type Owner +++ teledb t table user1 (1 row) 修改字段名 plaintext teledb d+ t Table "teledb.t" Column Type Collation Nullable Default Storage Stats target Description +++++++ id integer not null plain mc text extended Indexes: "tpkey" PRIMARY KEY, btree (id) Distribute By: SHARD(id) Location Nodes: ALL DATANODES teledb alter table t rename mc to nickname; ALTER TABLE teledb d+ t Table "teledb.t" Column Type Collation Nullable Default Storage Stats target Description +++++++ id integer not null plain nickname text extended Indexes: "tpkey" PRIMARY KEY, btree (id) Distribute By: SHARD(id) Location Nodes: ALL DATANODES

本文为您介绍如何使用多字段索引。 plaintext teledb create table tmulidx (f1 int,f2 int,f3 int,f4 int); CREATE TABLE teledb create index tmulidxidx on tmulidx(f1,f2,f3); CREATE INDEX 多字段使用注意事项： or 查询条件 bitmap scan 最多支持两个不同字段条件。 plaintext teledb insert into tmulidx select t,t,t,t from generateseries(1,1000000) as t; INSERT 0 1000000 teledb analyze ; ANALYZE teledb explain select from tmulidx where f11 or f22 ; QUERY PLAN Remote Fast Query Execution (cost0.00..0.00 rows0 width0) Node/s: dn001, dn002 > Bitmap Heap Scan on tmulidx (cost7617.08..7621.07 rows2 width16) Recheck Cond: ((f1 1) OR (f2 2)) > BitmapOr (cost7617.08..7617.08 rows2 width0) > Bitmap Index Scan on tmulidxidx (cost0.00..2.43 rows1 width0) Index Cond: (f1 1) > Bitmap Index Scan on tmulidxidx (cost0.00..7614.65 rows1 width0) Index Cond: (f2 2) (9 rows) Time: 5.134 ms teledb explain select from tmulidx where f11 or f22 or f13 ; QUERY PLAN Remote Fast Query Execution (cost0.00..0.00 rows0 width0) Node/s: dn001, dn002 > Bitmap Heap Scan on tmulidx (cost7619.51..7625.49 rows3 width16) Recheck Cond: ((f1 1) OR (f2 2) OR (f1 3)) > BitmapOr (cost7619.51..7619.51 rows3 width0) > Bitmap Index Scan on tmulidxidx (cost0.00..2.43 rows1 width0) Index Cond: (f1 1) > Bitmap Index Scan on tmulidxidx (cost0.00..7614.65 rows1 width0) Index Cond: (f2 2) > Bitmap Index Scan on tmulidxidx (cost0.00..2.43 rows1 width0) Index Cond: (f1 3) (11 rows) Time: 5.048 ms teledb

本文为您介绍如何管理表达式索引。 plaintext teledb create table tupper(id int,mc text); CREATE TABLE teledb create index tuppermc on tupper(mc); CREATE INDEX teledb insert into tupper select t,md5(t::text) from generateseries(1,10000) as t; INSERT 0 10000 teledb analyze tupper; ANALYZE teledb explain select from tupper where upper(mc)md5('1'); QUERY PLAN Remote Fast Query Execution (cost0.00..0.00 rows0 width0) Node/s: dn01, dn02 > Seq Scan on tupper (cost0.00..133.58 rows25 width37) Filter: (upper(mc) 'c4ca4238a0b923820dcc509a6f75849b'::text) (4 rows) teledb create index tuppermc on tupper(upper(mc)); ERROR: relation "tuppermc" already exists teledb create index tuppermc1 on tupper(upper(mc)); CREATE INDEX teledb explain select from tupper where upper(mc)md5('1'); QUERY PLAN Remote Fast Query Execution (cost0.00..0.00 rows0 width0) Node/s: dn01, dn02 > Bitmap Heap Scan on tupper (cost4.48..50.94 rows25 width37) Recheck Cond: (upper(mc) 'c4ca4238a0b923820dcc509a6f75849b'::text) > Bitmap Index Scan on tuppermc1 (cost0.00..4.47 rows25 width0) Index Cond: (upper(mc) 'c4ca4238a0b923820dcc509a6f75849b'::text) (6 rows)

本文为您介绍如何使用查询结果创建数据表。 plaintext teledb insert into t values(1,'teledb'); INSERT 0 1 teledb create table tas as select from t; INSERT 0 1 teledb select from tas; id mc + 1 teledb (1 row)

本文为您介绍如何管理普通索引。 plaintext teledb create index tididx on t1 using btree(id); CREATE INDEX

本文为您介绍如何添加分区子表。 plaintext teledb d+ trange Table "public.trange" Column Type Collation Nullable Default Storage Stats target Description +++++++ f1 bigint plain f2 timestamp without time zone now() plain f3 integer plain Distribute By: SHARD(f1) Location Nodes: ALL DATANODES Partition By: RANGE(f3) Of Partitions: 3 Start With: 1 Interval Of Partition: 50 teledb alter table trange add partitions 2; ALTER TABLE teledb d+ trange Table "public.trange" Column Type Collation Nullable Default Storage Stats target Description +++++++ f1 bigint plain f2 timestamp without time zone now() plain f3 integer plain Distribute By: SHARD(f1) Location Nodes: ALL DATANODES Partition By: RANGE(f3) Of Partitions: 5 Start With: 1 Interval Of Partition: 50

本文为您介绍如何指定模式创建表。 plaintext teledb create table public.t1(id int,mc text); CREATE TABLE

d+ tnativemullistgd Table "public.tnativemullistgd" Column Type Collation Nullable Default Storage Stats target Description ++++++ + f1 bigint not null nextval('tnativemullistf1seq'::regclass) plain f2 integer plain f3 text extended f4 text extended f5 timestamp(0) without time zone plain Partition of: tnativemullist FOR VALUES IN ('广东') Partition constraint: ((f3 IS NOT NULL) AND (f3 ANY (ARRAY['广东'::text]))) Partition key: RANGE (f5) Partitions: tnativemullistgd201701 FOR VALUES FROM ('20170101 00:00:00') TO ('20170201 00:00:00'), tnativemullistgd201702 FOR VALUES FROM ('20170201 00:00:00') TO ('20170301 00:00:00') Distribute By: SHARD(f1) Location Nodes: ALL DATANODES TeleDB支持存在1级和2级分区混用，大家不需要都平级。

本文介绍如何管理存储组，包括创建存储组、初始化创建sharding、删除存储组、修改存储组和查看存储组相关信息。 TeleDB中存储组将不同的dn节点组成不同的存储组，不同的存储组之间数据隔离。 创建存储组 将多个dn组成一个group plaintext 创建默认存储组 create default node group groupname with (dn1,dn2...) 创建普通存储组 create node group groupname with (dn1,dn2...) 初始化创建sharding 在存储组创建sharding之后，才能创建表，插入数据 plaintext teledb CREATE sharding group to group defaultgroup; CREATE SHARDING GROUP teledb clean sharding; CLEAN SHARDING 说明 TeleDB实例创建成功后，默认会将所有dn节点组成一个默认存储组defaultgroup 如果不存在默认存储组，则建表时需指定存储组 如果没有任何存储组，则不允许创建表 create sharding map创建的为主shard map, 当主shard map存在时，该命令会报错 主shard map已经存在时，后续新增一个存储组，需要通过下述命令创建扩展shard map plaintext teledb create extension sharding group to group group2; CREATE SHARDING GROUP 删除存储组 plaintext drop node group groupname 如果group中已经存在sharding，会抛出异常，需要先删除sharding； 如果group中存在表等对象，删除sharding也会失败，需先清空所有对象。 plaintext teledb drop node group defaultgroup; ERROR: shard info exist in group:defaultgroup groupoid:49156 删除sharding teledb drop sharding in group defaultgroup; ERROR: node group defaultgroup still has relations inside, please remove them first. 清空表和sharding之后可正常删除节点组 plaintext teledb

本文为您介绍如何创建分区表。 创建范围分区表 plaintext teledb create table trange (f1 bigint,f2 timestamp default now(), f3 integer) partition by range (f3) begin (1) step (50) partitions (3) distribute by shard(f1); CREATE TABLE teledb insert into trange(f1,f3) values(1,1),(2,50),(3,100),(2,110); COPY 4 teledb insert into trange(f1,f3) values(1,1),(2,50),(3,100),(2,110); COPY 4 teledb d+ trange; Table "public.trange" Column Type Collation Nullable Default Storage Stats target Description +++++++ f1 bigint plain f2 timestamp without time zone now() plain f3 integer plain Distribute By: SHARD(f1) Location Nodes: ALL DATANODES Partition By: RANGE(f3) Of Partitions: 3 Start With: 1 Interval Of Partition: 50 创建时间范围分区表 plaintext teledb create table ttimerange (f1 bigint, f2 timestamp ,f3 bigint) partition by range (f2) begin (timestamp without time zone '20170901 0:0:0') step (interval '1 month') partitions (12) distribute by shard(f1); CREATE TABLE teledb d+ ttimerange Table "public.ttimerange" Column Type Collation Nullable Default Storage Stats target Description +++++++ f1 bigint plain f2 timestamp without time zone plain f3 bigint plain Distribute By: SHARD(f1) Location Nodes: ALL DATANODES Partition By: RANGE(f2)

本文为您介绍如何删除模式。 plaintext teledb drop schema teledbschemaowner; DROP SCHEMA 当模式中存在对象时，则会删除失败，提示如下。 plaintext teledb create table teledbschemanew.test(id int); CREATE TABLE teledb drop schema teledbschemanew; ERROR: cannot drop schema teledbschemanew because other objects depend on it DETAIL: table teledbschemanew.test depends on schema teledbschemanew HINT: Use DROP ... CASCADE to drop the dependent objects too. 参考如下强制删除，会将模式中的对象也级联删除掉。 plaintext teledb drop schema teledbschemanew cascade; NOTICE: drop cascades to table teledbschemanew.test DROP SCHEMA

select from tjsonb; id fjsonb + 1 {"col": "pgxz", "col1": 1, "col2": "teledb"} 2 {"col1": 1, "col2": "teledb"} 3 {"col1": 1, "col2": "teledbupdate"} (3 rows) teledb update tjsonb set fjsonb jsonbset( fjsonb , '{col2}' , '"pgxz"' , false ) where id3; UPDATE 1 teledb select from tjsonb; id fjsonb + 1 {"col": "pgxz", "col1": 1, "col2": "teledb"} 2 {"col1": 1, "col2": "teledb"} 3 {"col1": 1, "col2": "pgxz"} (3 rows) jsonb函数应用 jsonbeach() 将 json 对象转变键和值 plaintext teledb select fjsonb from tjsonb where id1; fjsonb {"col": "pgxz", "col1": 1, "col2": "teledb"} (1 row) teledb select from jsonbeach((select fjsonb from tjsonb where id1)); key value + col "pgxz" col1 1 col2 "teledb" (3 rows) jsonbeachtext() 将 json 对象转变文本类型的键和值 plaintext teledb select from jsonbeachtext((select fjsonb from tjsonb where id1)); key value + col pgxz col1 1 col2 teledb (3 rows) rowtojson() 将一行记录变成一个json对象 plaintext teledb create table t1(id int, name varchar); CREATE TABLE teledb insert into t1 values(1,'teledb'),(2,'pgxc'); COPY 2 teledb select from t1; id name + 1 teledb 2 pgxc (2 rows) teledb select rowtojson(t1) from t1; rowtojson {"id":1,"name":"teledb"} {"id":2,"name":"pgxc"} (2 rows)

本文为您介绍json应用的相关操作。 创建json 类型字段表 plaintext teledb create table tjson(id int,fjson json); CREATE TABLE 插入数据 plaintext teledb insert into tjson values(1,'{"col1":1,"col2":"teledb"}'); INSERT 0 1 teledb insert into tjson values(2,'{"col1":1,"col2":"teledb","col3":"pgxz"}'); INSERT 0 1 teledb select from tjson; id fjson + 1 {"col1":1,"col2":"teledb"} 2 {"col1":1,"col2":"teledb","col3":"pgxz"} (2 rows) 通过键获得json对象域 plaintext teledb select fjson >'col2' as col2 ,fjson > 'col3' as col3 from tjson; col2 col3 + "teledb" "teledb" "pgxz" (2 rows) 以文本形式获取对象值 plaintext teledb select fjson >>'col2' as col2 ,fjson >> 'col3' as col3 from tjson; col2 col3 + teledb teledb pgxz (2 rows) teledb select fjson >>'col2' as col2 ,fjson >> 'col3' as col3 from tjson where fjson >> 'col3' is not null; col2 col3 + teledb pgxz (1 row)

select from teledbpg order by md5(nickname); id nickname + 1 hello,pgxc 3 pg 1 teledb (3 rows) 排序也能用子查询。 plaintext teledb select from teledbpg order by (select id from teledbpg order by random() limit 1); id nickname + 1 teledb 1 hello,pgxc 3 pg (3 rows) null 值排序结果处理 plaintext teledb insert into teledbpg values(4,null); INSERT 0 1 null 值记录排在最前面。 plaintext teledb select from teledbpg order by nickname nulls first; id nickname + 4 1 hello,pgxc 3 pg 1 teledb (4 rows) null 值记录排在最后。 plaintext teledb select from teledbpg order by nickname nulls last; id nickname + 1 hello,pgxc 3 pg 1 teledb 4 (4 rows) 按拼音排序 使用convert 函数实现汉字按拼音进行排序。 plaintext teledb select from (values ('张三'), ('李四'),('陈五')) t(myname) order by convert(myname::bytea,'UTF8','GBK'); myname 陈五 李四 张三 (3 rows) 使用convertto 函数实现汉字按拼音进行排序。 plaintext teledb select from (values ('张三'), ('李四'),('陈五')) t(myname) order by convertto(myname,'GBK'); myname 陈五 李四 张三 (3 rows) 通过指定排序规则collact 来实现汉字按拼音进行排序。 plaintext teledb

本文介绍如何在使用SELECT语法时，返回两个结果的交集。 plaintext teledb select from teledbpg intersect select from teledbpg1; id nickname + 3 pg (1 row)

当安装包与系统版本不匹配导致安装失败时，您可以参考本文，查看问题现象、原因和解决方案。 问题现象 安装dcp控制体出现安装报错，执行删除冲突的安装包，但删除不了。 原因分析 安装包与操作系统版本不一致，操作系统版本过高导致的。 解决方案 升级安装包，使其匹配操作系统版本。

select from tnew; f1 f2new f3 ++ 1 20230822 11:06:16.9783 1 3 20230822 11:06:16.9783 100 2 20230822 11:06:16.9783 50 2 20230822 11:06:16.9783 110 5 20230822 11:16:06.712109 10 (5 rows) teledb select from trangemv; f1 f2new + 1 20230822 3 20230822 2 20230822 2 20230822 (4 rows) teledb REFRESH MATERIALIZED VIEW trangemv; REFRESH MATERIALIZED VIEW teledb select from trangemv; f1 f2new + 1 20230822 2 20230822 2 20230822 5 20230822 3 20230822 (5 rows) 注意 物化视图数据存储在CN节点上面，每个CN节点各有一份相同的数据。 plaintext teledb explain select from trangemv; QUERY PLAN Seq Scan on trangemv (cost0.00..22.70 rows1270 width12) (1 row)

本文介绍如何在使用SELECT语法时，返回两个结果的交集。 plaintext teledb select from teledbpg intersect select from teledbpg1; id nickname + 3 pg (1 row)

本文介绍使用SELECT语法时，not in中包含了null，结果全为真的场景。 plaintext teledb select from teledbpg where id not in (1,3); id nickname + 2 TELEDB 4 (2 rows) teledb select from teledbpg where id not in (1,3,null); id nickname + (0 rows)