NebulaGraph v3.0.0 Release Note

NebulaGraph v3.0.0 is here! The new version introduced a series of new features including enhanced backup and restore, better support for the openCypher query language, and more fine-grained user management.

Features

Support backup and restore. #3469 #1 #22
Support openCypher queries with multiple MATCH statements. #3519 #3318
Support Standalone NebulaGraph. #3310
Support key value separation for the storage engine. #3281
Support topN push down for LOOKUP. #3499
Support vertex without tag. #3316 #3335 #3328 #3286
Support parameterized queries. #3379
Support queries without specifying VIDs but a LIMIT clause must be used to restrict the number of results. #3320 #3329 #3262
Support duration. #3338
Support most UTF-8 encoded characters of 1 to 4 bytes in Schema. #3380 #3440
Support DESCRIBE USER. #3300

Optimizations

Refactor cluster management. #3343
Add log monitor to check free bytes for log disks, change log level when your graph space is almost full. #3576
Support any string for tag names in apostrophe. #3424
Support that the storage service sends partition disk paths to the meta. #3369 #3416
Add constraints on invalid password attempts. #3573 #3629
Support DELETE in TOSS. #3374
Support to use logrotate. #3541
Support more metrics. #3446 #3605 #3590
Enhancement date and time parser. #3179
Remove read lock in the meta service to reduce the side effect of read-write locks. #3256
Refactor storage indexes to solve the coupling problem between services. #3196
Support specifying the floating point accuracy of the round() function. #3178ß
Support HTTPS for the ES client. #3150
Move version info outside of heartbeat. #3378
Support empty list, set, and map. #3302
Support specifying s2 region coverage parameters when creating a geo index. #3396
Add version info for SHOW HOSTS. #3702

Bugfix

Fix the bug that memory is not released when a default value is used and no value is specified in nGQL. #3666
Fix the bug that the function coalesce() cannot be used. #3653
Fix the bug that using multiple INSERT on an indexed tag will lead to incorrect LOOKUP results. #3627
Fix the crash when the expression exceeds the depth. #3606
Disable the aggregate function in the YIELD and WHERE clauses of nGQL. #3597
Fix the crash when using the aggregate function in UNWILD and WHERE clauses. #3397 #3355
Fix the bug that the tag index is rebuilt with an old schema version value. #3332
Fix the bug that the query results will still contain the expired edges if we use GO...REVERSELY. #3536
Fix the memory estimation error info in CentOS 6.0. #3534
Fix the crash when the LOOKUP statement contains a filter that consists of a logical And expression and an IN expression with only one element. #3525
Fix the bug that metad progress is suspended under heavy load. #3482
Fix the unwinding subgraph crash. #3506
Fix the DROP SPACE crash when rebuilding an index. #3406
Fix the bug of reading memory stats under cgroup v2. #3419
Fix the bug that DROP TAG INDEX deletes the edge index with the same name unexpectedly, and vice versa for the deletion of the tag index. #3413
Fix the bug that edges are not shown after a graph space is cloned. #3351
Fix the index existence check problem. #3315
Fix a bug that running the ALTER statement to query the type property may lead to a null pointer obtained by the graph service. #3325
Optimized the Raft to make the system more stable. #3172 #3435 #3358 #3322 #3031
Cancel memory check when the ratio is greater than 1.0. #3289
Fix the error with ninja-build. #3195
Fix the bug that creating tag and edge with the same name at the same time may both succeed. #3735
Fix the full-text index creation failure when there are the same tags or edges in different spaces. #3747
Fix variable inconsistency in YIELD clauses and GO statements. #3430
Fix the crash when schema version is greater than 256. #3893

Incompatibility

NebulaGraph 3.0.0 does not support most ecosystem tools of v2.x, please upgrade the ecosystem tools.
Storage services defined in the configuration files cannot be read or written directly. The configuration files only register the storage services into the meta services. You must run the ADD HOSTS command to read and write data on storage servers. #3343
Disable ZONE and GROUP. #3776 #3825 #3330
Disable BALANCE DATA. #3756
Modify the default session timeout from 0 to 28800 seconds, limit the value to between 1 and 604800 seconds. #3357 #3807
Add SHOW LOCAL SESSIONS and SHOW LOCAL QUERIES commands, and deprecate SHOW ALL QUERIES. #3488
A tag is not required for a vertex. DELETE VERTEX only deletes the vertices and does not delete the related outgoing and incoming edges of the vertices. At this time, there will be hanging edges by default. #3316 #3335 #3328 #3286
Disable the YIELD clause to return custom variables. #3271
The YIELD clause is required in the FETCH, GO, LOOKUP, FIND PATH and GET SUBGRAPH statements. #2957 #3056 #3139
Add non-reserved keywords: s2_max_level, s2_max_cells. #3396
It is required to specify a tag to query properties of a vertex in a MATCH statement. For example, from return v.name to return v.player.name. #3255

If you encounter any problems in the process of using NebulaGraph, please refer to NebulaGraph Database Manual to troubleshoot the problem. It records in detail the knowledge points and specific usage of the graph database and the graph database NebulaGraph.

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