[ https://issues.apache.org/jira/browse/DRILL-5697?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16133511#comment-16133511 ]
ASF GitHub Bot commented on DRILL-5697: --------------------------------------- Github user paul-rogers commented on a diff in the pull request: https://github.com/apache/drill/pull/907#discussion_r134035411 --- Diff: exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/StringFunctions.java --- @@ -57,22 +57,120 @@ private StringFunctions() {} @Output BitHolder out; @Workspace java.util.regex.Matcher matcher; @Workspace org.apache.drill.exec.expr.fn.impl.CharSequenceWrapper charSequenceWrapper; + @Workspace org.apache.drill.exec.expr.fn.impl.RegexpUtil.sqlPatternInfo patternInfo; @Override public void setup() { - matcher = java.util.regex.Pattern.compile(org.apache.drill.exec.expr.fn.impl.RegexpUtil.sqlToRegexLike( // - org.apache.drill.exec.expr.fn.impl.StringFunctionHelpers.toStringFromUTF8(pattern.start, pattern.end, pattern.buffer))).matcher(""); + patternInfo = org.apache.drill.exec.expr.fn.impl.RegexpUtil.sqlToRegexLike( + org.apache.drill.exec.expr.fn.impl.StringFunctionHelpers.toStringFromUTF8(pattern.start, pattern.end, pattern.buffer)); charSequenceWrapper = new org.apache.drill.exec.expr.fn.impl.CharSequenceWrapper(); - matcher.reset(charSequenceWrapper); + + // Use java regex and compile pattern only if it is not a simple pattern. + if (patternInfo.getPatternType() == org.apache.drill.exec.expr.fn.impl.RegexpUtil.sqlPatternType.NOT_SIMPLE) { --- End diff -- You have an enum to describe the cases, and a class to capture the info. That is the perfect place to encode the information about how to process. In particular, the pattern class should act as a factory for a pattern executor: will create an instance of the class needed to do the work. That will also allow this stuff to be unit tested without needing all of Drill. > Improve performance of filter operator for pattern matching > ----------------------------------------------------------- > > Key: DRILL-5697 > URL: https://issues.apache.org/jira/browse/DRILL-5697 > Project: Apache Drill > Issue Type: Improvement > Components: Execution - Flow > Affects Versions: 1.11.0 > Reporter: Padma Penumarthy > Assignee: Padma Penumarthy > > Queries using filter with sql like operator use Java regex library for > pattern matching. However, for cases like %abc (ends with abc), abc% (starts > with abc), %abc% (contains abc), it is observed that implementing these cases > with simple code instead of using regex library provides good performance > boost (4-6x). Idea is to use special case code for simple, common cases and > fall back to Java regex library for complicated ones. That will provide good > performance benefit for most common cases. -- This message was sent by Atlassian JIRA (v6.4.14#64029)