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ASF GitHub Bot commented on DRILL-5899: --------------------------------------- Github user paul-rogers commented on a diff in the pull request: https://github.com/apache/drill/pull/1015#discussion_r149555002 --- Diff: exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/SqlPatternEndsWithMatcher.java --- @@ -17,33 +17,30 @@ */ package org.apache.drill.exec.expr.fn.impl; -public class SqlPatternEndsWithMatcher implements SqlPatternMatcher { - final String patternString; - CharSequence charSequenceWrapper; - final int patternLength; - - public SqlPatternEndsWithMatcher(String patternString, CharSequence charSequenceWrapper) { - this.charSequenceWrapper = charSequenceWrapper; - this.patternString = patternString; - this.patternLength = patternString.length(); +import io.netty.buffer.DrillBuf; + +public class SqlPatternEndsWithMatcher extends AbstractSqlPatternMatcher { + + public SqlPatternEndsWithMatcher(String patternString) { + super(patternString); } @Override - public int match() { - int txtIndex = charSequenceWrapper.length(); - int patternIndex = patternLength; - boolean matchFound = true; // if pattern is empty string, we always match. + public int match(int start, int end, DrillBuf drillBuf) { + + if ( (end - start) < patternLength) { // No match if input string length is less than pattern length. + return 0; + } // simplePattern string has meta characters i.e % and _ and escape characters removed. // so, we can just directly compare. - while (patternIndex > 0 && txtIndex > 0) { - if (charSequenceWrapper.charAt(--txtIndex) != patternString.charAt(--patternIndex)) { - matchFound = false; - break; + for (int index = 1; index <= patternLength; index++) { --- End diff -- ``` int txtStart = end - patternLength; if (txtStart < start) { return 0; } for (int index = 0; index < patternLength; index++) { ... patternByteBuffer.get(index) ... drillBuf.getByte(txtStart + index) ... ``` > Simple pattern matchers can work with DrillBuf directly > ------------------------------------------------------- > > Key: DRILL-5899 > URL: https://issues.apache.org/jira/browse/DRILL-5899 > Project: Apache Drill > Issue Type: Improvement > Components: Execution - Flow > Reporter: Padma Penumarthy > Assignee: Padma Penumarthy > Priority: Critical > > For the 4 simple patterns we have i.e. startsWith, endsWith, contains and > constant,, we do not need the overhead of charSequenceWrapper. We can work > with DrillBuf directly. This will save us from doing isAscii check and UTF8 > decoding for each row. > UTF-8 encoding ensures that no UTF-8 character is a prefix of any other valid > character. So, instead of decoding varChar from each row we are processing, > encode the patternString once during setup and do raw byte comparison. > Instead of bounds checking and reading one byte at a time, we get the whole > buffer in one shot and use that for comparison. > This improved overall performance for filter operator by around 20%. -- This message was sent by Atlassian JIRA (v6.4.14#64029)