CREATE TABLE |
- Specify the NULL or NOT NULL attribute for columns.
- Specify the default value for a column.
- Create tables with the primary keys or unique keys.
- Create partitioned tables. Only RANGE-partitioned tables are supported.
- Generate columns.
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- Add foreign keys.
- Add table-level or column-level CHECK constraints.
- Set hidden columns.
- Limitations on partitions:
- A partition cannot be a right-closed interval. If a partition is a right-closed interval without using EXCLUSIVE to exclude the right boundary value, data conversion is not supported. In this case, the table schema is retained, but the partition information is lost.
- The every() method is not supported. If you use the every() method, the table schema is retained, but the partition information is lost.
- MySQL tenants of OceanBase Database do not support using columns of the DATETIME or TIMESTAMP type as the partitioning key.
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ALTER TABLE |
- Columns
- Add multiple columns.
- Drop one or more columns.
- Change the column type.
- Modify the column length.
Notice
Make sure that the length after modification is greater than that before modification.
- Modify or delete the default value of a column.
Notice
The column value cannot be null.
- Specify the NULL or NOT NULL attribute for columns.
- Specify the default value for a column.
- Partitions
Add partitions on the condition that each expression contains EXCLUSIVE.
- Constraints
You can specify UNIQUE constraints.
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- Columns
- Modify or delete the NOT NULL attribute.
- Specify a column as the primary key.
- Specify
CHECK constraints.
- Add or drop foreign keys.
- Rename columns.
- Partitions
- Add partitions if any expression does not contain EXCLUSIVE.
- Detach partitions.
- Attach partitions.
- Constraints
- Add or drop the primary key.
- Add or drop the CHECK constraint.
- Drop the unique key.
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DROP TABLE |
Drop a table. |
None |
TRUNCATE TABLE |
Truncate a table. |
None |
RENAME TABLE |
Rename a table. |
None |
CREATE INDEX |
- Create a normal index or a unique index.
- Create a partitioned index.
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- Sort data in descending order. This operation is not supported because the DESC keyword is lost.
- Use clustered indexes. This operation is not supported because the cluster information is lost.
- Use reverse indexes. This operation is not supported because the reverse key is lost.
- Merge or split indexed pages.
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DROP INDEX |
None |
Drop an index. |
RENAME INDEX |
None |
Rename an index. |
ADD COMMENT/DROP COMMENT |
Add and drop table-level comments. |
Add or drop column-level comments. |
