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Version: 0.6

ALTER

ALTER can be used to modify any table settings or data within the table:

  • Add/Drop a column
  • Rename a table

Syntax

ALTER TABLE [db.]table
[ADD COLUMN name type [options]
| DROP COLUMN name
| RENAME name
]

Examples

Add column

Adds a new column to the table:

ALTER TABLE monitor ADD COLUMN load_15 double;

Definition of column is the same as in CREATE.

We can set the new column's location. In first position for example:

ALTER TABLE monitor ADD COLUMN load_15 double FIRST;

After an existing column:

ALTER TABLE monitor ADD COLUMN load_15 double AFTER memory;

Adds a new column as a tag(primary key) with a default value:

ALTER TABLE monitor ADD COLUMN app STRING DEFAULT 'shop' PRIMARY KEY;

Remove column

Removes a column from the table:

ALTER TABLE monitor DROP COLUMN load_15;

The removed column can't be retrieved immediately by all subsequent queries.

Rename table

Renames the table:

ALTER TABLE monitor RENAME monitor_new;

This command only renames the table; it doesn't modify the data within the table.