vpruthi/doc-exports
1
0
Fork 0
forked from docs/doc-exports
Code Pull Requests Activity
doc-exports/docs/ddm/umn/ddm_08_0013.html
Ru, Li Yi 4b09a03a51 ddm_umn 
Reviewed-by: Wagner, Fabian <fabian.wagner@t-systems.com>
Co-authored-by: Ru, Li Yi <liyiru7@huawei.com>
Co-committed-by: Ru, Li Yi <liyiru7@huawei.com>
2024-04-11 11:39:26 +00:00

3.1 KiB
Raw Permalink Blame History

Use Constraints

DDM is compatible with the MySQL license and syntax, but the use of SQL statements is limited due to differences between distributed databases and single-node databases.

Unsupported SQL Statements

  • Triggers
  • Temporary tables
  • DO statement
  • Association with foreign keys
  • RESET statement
  • FLUSH statement
  • BINLOG statement
  • HANDLER statement
  • SHOW WARNINGS statement
  • Assignment operator :=
  • Operators less than (<), assignment (=), and more than (>)
  • Expression IS UNKNOWN
  • INSTALL and UNINSTALL PLUGIN statements
  • Cross-shard stored procedures and custom functions
  • Statements for modifying database names, table names, and sharding field names and types
  • Most of SHOW statements such as SHOW PROFILES and SHOW ERRORS
  • Table maintenance statements, including ANALYZE, CHECK, CHECKSUM, OPTIMIZE, and REPAIR TABLE
  • Statements for assigning a value to or querying variable session, for example, set @rowid=0;select @rowid:=@rowid+1,id from user
  • SQL statements that use -- or /*...*/ to comment out a single line or multiple lines of code
  • The result of the REPEAT function contains a maximum of 1,000,000 characters (in version 3.0.9 or later).

Permission Levels

Permission levels supported by DDM are as follows:

  • Global level (not supported)
  • Database level (supported)
  • Table level (supported)
  • Column level (not supported)
  • Subprogram level (not supported)
  • User level (supported)
Parent topic: SQL Syntax