我目前有一个匹配世界的边界正则表达式
const trigger = 'foo1 foo2'
const rx = new RegExp(`\\b${trigger}\\b`, 'i');
return rx.test(text);
这符合以下情况：
foo1 foo2 <-- exact match
bar foo1 foo2 <-- end of sentence
foo1 foo2 bar <-- beginning of sentence
不是
barfoo1 foo2
foo1 foo2bar
barfoo1 foo2bar
这正是我想要的标准字符串的行为
但是，当trigger变成#foo时，这将不起作用，因为#对于单词边界无效。
正则表达式由我的服务器控制，但触发器由用户控制。
仅当字符串以井号标签开头时，这才是问题，因此类似foo1 #foo2的方法仍然有效。我总是可以在一开始就删除主题标签。
如何使正则表达式同时支持单词和主题标签？
答案 0 :(得分：0)
您可以使用val df = spark.sql("SELECT * FROM dev_bm_bda_stg.ana_tfd_avr limit 100")
代替左边界，而使用org.apache.spark.sql.AnalysisException: Table or view not found: `mydatabase`.`mytable`; line 1 pos 14;
'GlobalLimit 10
+- 'LocalLimit 10
+- 'Project [*]
+- 'UnresolvedRelation `mydatabase`.`mytable`
at org.apache.spark.sql.catalyst.analysis.package$AnalysisErrorAt.failAnalysis(package.scala:42)
at org.apache.spark.sql.catalyst.analysis.CheckAnalysis$$anonfun$checkAnalysis$1.apply(CheckAnalysis.scala:80)
at org.apache.spark.sql.catalyst.analysis.CheckAnalysis$$anonfun$checkAnalysis$1.apply(CheckAnalysis.scala:76)
at org.apache.spark.sql.catalyst.trees.TreeNode.foreachUp(TreeNode.scala:128)
at org.apache.spark.sql.catalyst.trees.TreeNode$$anonfun$foreachUp$1.apply(TreeNode.scala:127)
at org.apache.spark.sql.catalyst.trees.TreeNode$$anonfun$foreachUp$1.apply(TreeNode.scala:127)
at scala.collection.immutable.List.foreach(List.scala:381)
at org.apache.spark.sql.catalyst.trees.TreeNode.foreachUp(TreeNode.scala:127)
at org.apache.spark.sql.catalyst.trees.TreeNode$$anonfun$foreachUp$1.apply(TreeNode.scala:127)
at org.apache.spark.sql.catalyst.trees.TreeNode$$anonfun$foreachUp$1.apply(TreeNode.scala:127)
at scala.collection.immutable.List.foreach(List.scala:381)
at org.apache.spark.sql.catalyst.trees.TreeNode.foreachUp(TreeNode.scala:127)
at org.apache.spark.sql.catalyst.trees.TreeNode$$anonfun$foreachUp$1.apply(TreeNode.scala:127)
at org.apache.spark.sql.catalyst.trees.TreeNode$$anonfun$foreachUp$1.apply(TreeNode.scala:127)
at scala.collection.immutable.List.foreach(List.scala:381)
at org.apache.spark.sql.catalyst.trees.TreeNode.foreachUp(TreeNode.scala:127)
at org.apache.spark.sql.catalyst.analysis.CheckAnalysis$class.checkAnalysis(CheckAnalysis.scala:76)
at org.apache.spark.sql.catalyst.analysis.Analyzer.checkAnalysis(Analyzer.scala:57)
at org.apache.spark.sql.execution.QueryExecution.assertAnalyzed(QueryExecution.scala:48)
at org.apache.spark.sql.Dataset$.ofRows(Dataset.scala:63)
at org.apache.spark.sql.SparkSession.sql(SparkSession.scala:600)
at org.apache.spark.sql.SQLContext.sql(SQLContext.scala:699)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.apache.zeppelin.spark.SparkSqlInterpreter.interpret(SparkSqlInterpreter.java:116)
at org.apache.zeppelin.interpreter.LazyOpenInterpreter.interpret(LazyOpenInterpreter.java:97)
at org.apache.zeppelin.interpreter.remote.RemoteInterpreterServer$InterpretJob.jobRun(RemoteInterpreterServer.java:498)
at org.apache.zeppelin.scheduler.Job.run(Job.java:175)
at org.apache.zeppelin.scheduler.FIFOScheduler$1.run(FIFOScheduler.java:139)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
代替右边界：
(^|\s+)模式($|\s+)的问题在于const trigger = '#foo1';
text = 'hello #foo1 blah';
const rx = new RegExp(`(^|\\s+)${trigger}($|\\s+)`, 'i');
console.log(rx.test(text));
已经是非文字字符。因此\b#foo1\b将不会在哈希符号前面的空格处出现。