ALTER TABLE

ALTER TABLE can change the schema or options of a table.

ALTER TABLE SCHEMA

HoraeDB current supports ADD COLUMN to alter table schema.

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-- create a table and add a column to it
CREATE TABLE `t`(a int, t timestamp NOT NULL, TIMESTAMP KEY(t)) ENGINE = Analytic;
ALTER TABLE `t` ADD COLUMN (b string);

It now becomes:

-- DESCRIBE TABLE `t`;

name    type        is_primary  is_nullable is_tag

t       timestamp   true        false       false
tsid    uint64      true        false       false
a       int         false       true        false
b       string      false       true        false

ALTER TABLE OPTIONS

HoraeDB current supports MODIFY SETTING to alter table schema.

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-- create a table and add a column to it
CREATE TABLE `t`(a int, t timestamp NOT NULL, TIMESTAMP KEY(t)) ENGINE = Analytic;
ALTER TABLE `t` MODIFY SETTING write_buffer_size='300M';

The SQL above tries to modify the write_buffer_size of the table, and the table’s option becomes:

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CREATE TABLE `t` (`tsid` uint64 NOT NULL, `t` timestamp NOT NULL, `a` int, PRIMARY KEY(tsid,t), TIMESTAMP KEY(t)) ENGINE=Analytic WITH(arena_block_size='2097152', compaction_strategy='default', compression='ZSTD', enable_ttl='true', num_rows_per_row_group='8192', segment_duration='', storage_format='AUTO', ttl='7d', update_mode='OVERWRITE', write_buffer_size='314572800')

Besides, the ttl can be altered from 7 days to 10 days by such SQL:

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ALTER TABLE `t` MODIFY SETTING ttl='10d';
Last modified August 21, 2024: refactor: use hugo to build website (#132) (36785ca)