INFORMATION_SCHEMA
INFORMATION_SCHEMA provides access to metadata such as database and table names and column data types. GreptimeDB also provides custom INFORMATION_SCHEMA tables for system, cluster, and runtime metadata.
Many INFORMATION_SCHEMA tables have a corresponding SHOW command. Unlike SHOW, INFORMATION_SCHEMA tables can be filtered, projected, and joined in SQL queries.
The tables below distinguish implemented metadata tables from compatibility tables that return no rows or are not supported.
Tables for MySQL compatibility
| Table Name | Description |
|---|---|
CHARACTER_SETS | provides information about available character sets. |
CHECK_CONSTRAINTS | Not implemented. Returns zero rows. |
COLLATIONS | Provides a list of collations that the server supports. |
COLLATION_CHARACTER_SET_APPLICABILITY | Explains which collations apply to which character sets. |
COLUMNS | Provides a list of columns for all tables. |
COLUMN_PRIVILEGES | Not implemented. Returns zero rows. |
COLUMN_STATISTICS | Not supported. |
ENGINES | Provides a list of supported storage engines. |
EVENTS | Not implemented. Returns zero rows. |
FILES | Not implemented. Returns zero rows. |
GLOBAL_STATUS | Not implemented. Returns zero rows. |
GLOBAL_VARIABLES | Not supported. |
KEY_COLUMN_USAGE | Describes the key constraints of the columns, such as the primary key, and time index constraint. |
OPTIMIZER_TRACE | Not implemented. Returns zero rows. |
PARAMETERS | Not implemented. Returns zero rows. |
PARTITIONS | Provides a list of table partitions. |
PLUGINS | Not supported. |
PROCESSLIST | Not supported, please use PROCESS_LIST instead. |
PROFILING | Not implemented. Returns zero rows. |
REFERENTIAL_CONSTRAINTS | Not implemented. Returns zero rows. |
ROUTINES | Not implemented. Returns zero rows. |
SCHEMATA | Provides similar information to SHOW DATABASES. |
SCHEMA_PRIVILEGES | Not implemented. Returns zero rows. |
SESSION_STATUS | Not implemented. Returns zero rows. |
SESSION_VARIABLES | Not supported. |
STATISTICS | Provides index metadata in a MySQL-compatible shape. |
TABLES | Provides a list of tables that the current user has visibility of. Similar to SHOW TABLES. |
TABLESPACES | Not supported. |
TABLE_PRIVILEGES | Not implemented. Returns zero rows. |
TRIGGERS | Not supported. GreptimeDB Enterprise provides a differently shaped TRIGGERS table. |
USER_ATTRIBUTES | Not supported. |
USER_PRIVILEGES | Not supported. |
VARIABLES_INFO | Not supported. |
VIEWS | Provides a list of views that the current user has visibility of. Similar to running SHOW FULL TABLES WHERE table_type = 'VIEW' |
TABLE_CONSTRAINTS | Provides time-index and primary-key constraint metadata. |
Tables that GreptimeDB provides
| Table Name | Description |
|---|---|
BUILD_INFO | Provides the system build info. |
REGION_PEERS | Provides details about where regions are stored. |
REGION_INFO | Provides Region runtime and manifest metadata, such as role and state, sequences, manifest version, Region options, SST format, and node ownership. |
REGION_STATISTICS | Provides details about region statistics info, such as disk size, etc. |
CLUSTER_INFO | Provides the topology information of the cluster. |
FLOWS | Provides the flow information. |
PROCEDURE_INFO | Procedure information. |
PROCESS_LIST | Running queries information. |
RECYCLE_BIN | Provides soft-dropped tables that are still eligible for restore. |
TABLE_SEMANTICS | Provides an experimental view over table semantic metadata. |
SSTS_INDEX_META | Provides SST index metadata including inverted indexes, fulltext indexes, and bloom filters. |
SSTS_MANIFEST | Provides SST file information from the manifest including file paths, sizes, time ranges, row counts, and encoded primary key ranges. |
SSTS_STORAGE | Provides SST file information from the storage layer for verification and debugging. |
TRIGGERS | Provides the trigger information. |
ALERTS | Provides the alert information. |