[branch-2.0-var](sample) Fix computeSampleTabletIds NullPointerException

[xinyiZzz]

Proposed changes

2023-11-05 22:52:01,914 WARN (mysql-nio-pool-167|1655) [StmtExecutor.analyze():992] Analyze failed. stmt[222101, ec1adf0f9f7b405d-8cb71a522bc50b82]
java.lang.NullPointerException: null
at org.apache.doris.planner.OlapScanNode.computeSampleTabletIds(OlapScanNode.java:952) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.OlapScanNode.init(OlapScanNode.java:548) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.SingleNodePlanner.createScanNode(SingleNodePlanner.java:2064) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.SingleNodePlanner.createTableRefNode(SingleNodePlanner.java:2213) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.SingleNodePlanner.createSelectPlan(SingleNodePlanner.java:1244) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.SingleNodePlanner.createQueryPlan(SingleNodePlanner.java:266) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.SingleNodePlanner.createSingleNodePlan(SingleNodePlanner.java:189) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.OriginalPlanner.createPlanFragments(OriginalPlanner.java:160) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.OriginalPlanner.plan(OriginalPlanner.java:101) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.StmtExecutor.analyzeAndGenerateQueryPlan(StmtExecutor.java:1141) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.StmtExecutor.analyze(StmtExecutor.java:975) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.StmtExecutor.executeByLegacy(StmtExecutor.java:673) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.StmtExecutor.execute(StmtExecutor.java:451) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.StmtExecutor.execute(StmtExecutor.java:422) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.ConnectProcessor.handleQuery(ConnectProcessor.java:435) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.ConnectProcessor.dispatch(ConnectProcessor.java:583) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.ConnectProcessor.processOnce(ConnectProcessor.java:834) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.mysql.ReadListener.lambda$handleEvent$0(ReadListener.java:52) ~[doris-fe.jar:1.2-SNAPSHOT]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[?:1.8.0_333]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[?:1.8.0_333]
at java.lang.Thread.run(Thread.java:750) ~[?:1.8.0_333]
2023-11-05 22:52:01,914 WARN (mysql-nio-pool-167|1655) [StmtExecutor.executeByLegacy():776] execute Exception. stmt[222101, ec1adf0f9f7b405d-8cb71a522bc50b82]
org.apache.doris.common.AnalysisException: errCode = 2, detailMessage = Unexpected exception: null
at org.apache.doris.qe.StmtExecutor.analyze(StmtExecutor.java:993) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.StmtExecutor.executeByLegacy(StmtExecutor.java:673) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.StmtExecutor.execute(StmtExecutor.java:451) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.StmtExecutor.execute(StmtExecutor.java:422) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.ConnectProcessor.handleQuery(ConnectProcessor.java:435) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.ConnectProcessor.dispatch(ConnectProcessor.java:583) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.qe.ConnectProcessor.processOnce(ConnectProcessor.java:834) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.mysql.ReadListener.lambda$handleEvent$0(ReadListener.java:52) ~[doris-fe.jar:1.2-SNAPSHOT]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[?:1.8.0_333]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[?:1.8.0_333]
at java.lang.Thread.run(Thread.java:750) ~[?:1.8.0_333]

Further comments

If this is a relatively large or complex change, kick off the discussion at dev@doris.apache.org by explaining why you chose the solution you did and what alternatives you considered, etc...

[xiaokang]

LGTM

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.