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https://github.com/timescale/timescaledb.git
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e85721a8ed
ONLY does not make semantic sense for hypertables. This commit blocks the use of this modifier.
52 lines
2.1 KiB
SQL
52 lines
2.1 KiB
SQL
CREATE TABLE alter_test(time timestamptz, temp float, color varchar(10));
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-- create hypertable with two chunks
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SELECT create_hypertable('alter_test', 'time', 'color', 2, chunk_time_interval => 2628000000000);
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INSERT INTO alter_test VALUES ('2017-01-20T09:00:01', 17.5, 'blue'),
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('2017-01-21T09:00:01', 19.1, 'yellow'),
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('2017-04-20T09:00:01', 89.5, 'green'),
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('2017-04-21T09:00:01', 17.1, 'black');
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SELECT * FROM test.show_columns('alter_test');
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SELECT * FROM test.show_columnsp('_timescaledb_internal.%chunk');
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-- show the column name and type of the partitioning dimension in the
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-- metadata table
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SELECT * FROM _timescaledb_catalog.dimension;
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EXPLAIN (costs off)
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SELECT * FROM alter_test WHERE time > '2017-05-20T10:00:01';
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-- rename column and change its type
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ALTER TABLE alter_test RENAME COLUMN time TO time_us;
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--converting timestamptz->timestamp should happen under UTC
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SET timezone = 'UTC';
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ALTER TABLE alter_test ALTER COLUMN time_us TYPE timestamp;
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RESET timezone;
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ALTER TABLE alter_test RENAME COLUMN color TO colorname;
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\set ON_ERROR_STOP 0
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-- Changing types on hash-partitioned columns is not safe for some
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-- types and is therefore blocked.
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ALTER TABLE alter_test ALTER COLUMN colorname TYPE text;
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\set ON_ERROR_STOP 1
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SELECT * FROM test.show_columns('alter_test');
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SELECT * FROM test.show_columnsp('_timescaledb_internal.%chunk');
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-- show that the metadata has been updated
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SELECT * FROM _timescaledb_catalog.dimension;
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-- constraint exclusion should still work with updated column
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EXPLAIN (costs off)
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SELECT * FROM alter_test WHERE time_us > '2017-05-20T10:00:01';
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\set ON_ERROR_STOP 0
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-- verify that we cannot change the column type to something incompatible
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ALTER TABLE alter_test ALTER COLUMN colorname TYPE varchar(3);
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-- conversion that messes up partitioning fails
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ALTER TABLE alter_test ALTER COLUMN time_us TYPE timestamptz USING time_us::timestamptz+INTERVAL '1 year';
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--ONLY blocked
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ALTER TABLE ONLY alter_test RENAME COLUMN colorname TO colorname2;
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ALTER TABLE ONLY alter_test ALTER COLUMN colorname TYPE varchar(10);
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\set ON_ERROR_STOP 1
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