These commands are primarily governed by database administrators that revolve around four primary commands i.e. Join (select id, sum(rows) as rows from stv_tbl_perm group by id) c on a.id=c. There are five basic types of SQL commands, namely: Data Definition Language (DDL): DDL commands are used to create, modify, and remove database objects. Join (select sum(capacity) as total from stv_partitions where part_begin=0) as part on 1=1 Join (select id, sum(rows) as rows from stv_tbl_perm group by id) c on a.id=c.id Join (select tbl, sum(decode(unsorted, 1, 1, 0)) as unsorted_mbytes, count(*) as mbytes from stv_blocklist group by tbl) b on a.id=b.tbl Join pg_namespace as pgns on pgns.oid = pgtbl.relnamespace Join pg_class as pgtbl on pgtbl.oid = a.id Select trim(pgdb.datname) as Database, trim(pgns.nspname) as Schema, trim(a.name) as Table,Ĭ.rows, ((b.mbytes/part.total::decimal)*100)::decimal(5,3) as pct_of_total, b.mbytes, b.unsorted_mbytes This includes database name, schema name, table name, total row count, size on disk and unsorted size: - sort by row count Modified versions of one of the other answers. Postgres | public | table_data1_1 | 7 | 1 Join pg_database as pgdb on pgdb.oid = a.db_idįrom stv_blocklist group by tbl) b on a.id=b.tblĭatabase | schema | table | mbytes | rows Join pg_namespace as pgn on pgn.oid = pgc.relnamespace it means 372 MB ? select trim(pgdb.datname) as Database, trim(pgn.nspname) as Schema,įrom ( select db_id, id, name, sum(rows) as rows from stv_tbl_perm a group by db_id, id, name ) as a Is there any alternate to find out like oracle ( from DBA_SEGMENTS )įor tble size, i have below query, but not sure about exact menaing of MBYTES. SELECT pg_size_pretty( pg_relation_size('table_name') ) How to find out database size, tablespace, schema size & table size ?īut below are not working in redshift ( for above version ) SELECT pg_database_size('db_name') To avoid the schema change mentioned above, you can use the intermediate table to add new column with correct data type.My redshift version is: PostgreSQL 8.0.2 on i686-pc-linux-gnu, compiled by GCC gcc (GCC) 3.4.2 20041017 (Red Hat 3.4.2-6.fc3), Redshift 1.0.735 ALTER the size of sname from TABLE Students. Here, we have changed the length of the student name from 10 to 100. In this example, we will increase the size of sname column on the TABLE Students. Alter Redshift Table column Data type using Intermediate Table The syntax for ALTER column to change the length in Amazon Redshift is as follows. This might cause problem if you are loading the data into this table using Redshift COPY command. The newly added column will be last in the tables. ALTER TABLE locks the table for read and write operations until the transaction enclosing the ALTER TABLE operation completes, unless it's specifically stated in the documentation that you can query data or perform other operations on the table while it is altered. In this approach, there will be a change in the table schema. There is another way to change redshift table column data type using intermediate table. create table sampleĪlter table sample add column age_new int Īlter table sample rename column age_new to age
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |