MOTService SQL Coverage and Limitations

MOTService supports most standard Postgres SQL and common database features, such as stored procedures and user-defined functions. In addition, when MOTService creates or modifies a table, the maximum size of the varchar field is 16 KB, and the maximum size of a single line is 56 KB.

The following tables list the features and data types that are not supported by MOTService:

**Table 1** Operations not supported by MOTService
Type	Operation
Features not supported by MOTService	Cross-engine (disk + MOT) queries, views, or transactions are not supported.
	No snapshot or serializable isolation is not supported.
	JIT compilation of some complex SQL statements (such as cursors) is not supported.
	The local memory is limited to 1 GB. A transaction can modify only less than 1 GB of data.
	The capacity (data and indexes) is limited by the available memory.
	Full-text index search is not supported.
	Logical replication is not supported.
Functions not supported by MOTService	Partitioning by range
	AES
	Stream operation
	User-defined type
	Sub-transaction
	DML trigger
	DDL trigger
DDL operations not supported by MOTService	Modifying the data type of a table schema, that is, ALTER COLUMN (Columns in the table schema can be added, deleted, and renamed.)
	Creating a including table
	Creating an as select table
	Partitioning by range
	Creating a table without a logging clause (no-logging clause)
	Creating a deferrable constraint primary key (DEFERRABLE)
	Reindexing
	Tablespace
	Creating a schema using subcommands
DMLs not supported by MOTService	Merge into
	Select into
	Lock table
	Copy from table
Indexes not supported by MOTService	Creating an index on decimal or numeric type
Indexes not supported by MOTService	Creating an index on a table whose key size is greater than 2 KB The key size includes the column size in bytes plus the column additional size, which is the overhead required to maintain the index. In addition, if the index is not unique, an additional 8 bytes are required.
Queries not supported by native compilation	More than two tables involved
Queries not supported by native compilation	Any of the following conditions is met: Aggregation of non-native types Window functions Subqueries or sublinks Distinct-ON modifier (distinct clause from DISTINCT ON) Recursion (with RECURSIVE specified) Modifying CTE (INSERT/UPDATE/DELETE included in WITH) Group By clause Grouping sets Having clause Windows clause Distinct clause Sort clause that does not conform to native index order Set operations Constraint dependencies

**Table 2** Data types not supported by MOTService
Data Type Name
User-Defined Type (UDF)	UUID	INET	Blob	Circle	Box
Array data type	Clob	CIDR	Raw	Reltime	Text
NVARCHAR2(n)	Name	BYTEA	Path	JSON	Line
Bit varying(10)	Tsvector	Bit	Tsquery	HSTORE	Point
Smalldatetime	MACADDR	Money	HSTORE	Varbit	LSEG
Any unlimited varchar/character varying	POLYGON	OID	-	-	-