SQL: Fix translation of LIKE/RLIKE keywords (#36672)

* SQL: Fix translation of LIKE/RLIKE keywords

Refactor Like/RLike functions to simplify internals and improve query
 translation when chained or within a script context.

Fix #36039
Fix #36584

Author: costin

x-pack/plugin/sql/qa/src/main/resources/agg.sql-spec

@@ -280,6 +280,8 @@ aggMaxWithAlias
 SELECT gender g, MAX(emp_no) m FROM "test_emp" GROUP BY g ORDER BY gender;
 aggMaxOnDate
 SELECT gender, MAX(birth_date) m FROM "test_emp" GROUP BY gender ORDER BY gender;
+aggAvgAndMaxWithLikeFilter
+SELECT CAST(AVG(salary) AS LONG) AS avg, CAST(SUM(salary) AS LONG) AS s FROM "test_emp" WHERE first_name LIKE 'G%';
 
 // Conditional MAX
 aggMaxWithHaving

x-pack/plugin/sql/qa/src/main/resources/datetime.sql-spec

@@ -119,7 +119,10 @@ SELECT DAY_OF_WEEK(birth_date) day, COUNT(*) c FROM test_emp WHERE DAY_OF_WEEK(b
 currentTimestampYear
 SELECT YEAR(CURRENT_TIMESTAMP()) AS result;
 
-currentTimestampMonth
+//
+// H2 uses the local timezone instead of the specified one
+//
+currentTimestampMonth-Ignore
 SELECT MONTH(CURRENT_TIMESTAMP()) AS result;
 
 currentTimestampHour-Ignore

x-pack/plugin/sql/qa/src/main/resources/filter.sql-spec

@@ -49,6 +49,8 @@ whereFieldWithNotEqualsOnString
 SELECT last_name l FROM "test_emp" WHERE emp_no < 10003 AND gender <> 'M';
 whereFieldWithLikeMatch
 SELECT last_name l FROM "test_emp" WHERE emp_no < 10003 AND last_name LIKE 'K%';
+whereFieldWithNotLikeMatch
+SELECT last_name l FROM "test_emp" WHERE emp_no < 10020 AND first_name NOT LIKE 'Ma%';
 
 whereFieldWithOrderNot
 SELECT last_name l FROM "test_emp" WHERE NOT emp_no < 10003 ORDER BY emp_no LIMIT 5;

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/expression/function/scalar/whitelist/InternalSqlScriptUtils.java

@@ -165,6 +165,7 @@ public static Object nullif(Object left, Object right) {
     // Regex
     //
     public static Boolean regex(String value, String pattern) {
+        // TODO: this needs to be improved to avoid creating the pattern on every call
         return RegexOperation.match(value, pattern);
     }
 

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/expression/predicate/regex/Like.java

@@ -11,26 +11,24 @@
 
 public class Like extends RegexMatch {
 
-    public Like(Location location, Expression left, LikePattern right) {
-        super(location, left, right);
-    }
+    private final LikePattern pattern;
 
-    @Override
-    protected NodeInfo<Like> info() {
-        return NodeInfo.create(this, Like::new, left(), pattern());
+    public Like(Location location, Expression left, LikePattern pattern) {
+        super(location, left, pattern.asJavaRegex());
+        this.pattern = pattern;
     }
 
     public LikePattern pattern() {
-        return (LikePattern) right();
+        return pattern;
     }
 
     @Override
-    protected Like replaceChildren(Expression newLeft, Expression newRight) {
-        return new Like(location(), newLeft, (LikePattern) newRight);
+    protected NodeInfo<Like> info() {
+        return NodeInfo.create(this, Like::new, field(), pattern);
     }
 
     @Override
-    protected String asString(Expression pattern) {
-        return ((LikePattern) pattern).asJavaRegex();
+    protected Like replaceChild(Expression newLeft) {
+        return new Like(location(), newLeft, pattern);
     }
 }

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/expression/predicate/regex/LikePattern.java

@@ -5,10 +5,6 @@
  */
 package org.elasticsearch.xpack.sql.expression.predicate.regex;
 
-import org.elasticsearch.xpack.sql.expression.LeafExpression;
-import org.elasticsearch.xpack.sql.tree.Location;
-import org.elasticsearch.xpack.sql.tree.NodeInfo;
-import org.elasticsearch.xpack.sql.type.DataType;
 import org.elasticsearch.xpack.sql.util.StringUtils;
 
 import java.util.Objects;
@@ -21,7 +17,7 @@
  *
  * To prevent conflicts with ES, the string and char must be validated to not contain '*'.
  */
-public class LikePattern extends LeafExpression {
+public class LikePattern {
 
     private final String pattern;
     private final char escape;
@@ -30,8 +26,7 @@ public class LikePattern extends LeafExpression {
     private final String wildcard;
     private final String indexNameWildcard;
 
-    public LikePattern(Location location, String pattern, char escape) {
-        super(location);
+    public LikePattern(String pattern, char escape) {
         this.pattern = pattern;
         this.escape = escape;
         // early initialization to force string validation
@@ -40,11 +35,6 @@ public LikePattern(Location location, String pattern, char escape) {
         this.indexNameWildcard = StringUtils.likeToIndexWildcard(pattern, escape);
     }
 
-    @Override
-    protected NodeInfo<LikePattern> info() {
-        return NodeInfo.create(this, LikePattern::new, pattern, escape);
-    }
-
     public String pattern() {
         return pattern;
     }
@@ -74,16 +64,6 @@ public String asIndexNameWildcard() {
         return indexNameWildcard;
     }
 
-    @Override
-    public boolean nullable() {
-        return false;
-    }
-
-    @Override
-    public DataType dataType() {
-        return DataType.KEYWORD;
-    }
-
     @Override
     public int hashCode() {
         return Objects.hash(pattern, escape);

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/expression/predicate/regex/RLike.java

@@ -6,28 +6,29 @@
 package org.elasticsearch.xpack.sql.expression.predicate.regex;
 
 import org.elasticsearch.xpack.sql.expression.Expression;
-import org.elasticsearch.xpack.sql.expression.Literal;
 import org.elasticsearch.xpack.sql.tree.Location;
 import org.elasticsearch.xpack.sql.tree.NodeInfo;
 
 public class RLike extends RegexMatch {
 
-    public RLike(Location location, Expression left, Literal right) {
-        super(location, left, right);
+    private final String pattern;
+
+    public RLike(Location location, Expression left, String pattern) {
+        super(location, left, pattern);
+        this.pattern = pattern;
     }
 
-    @Override
-    protected NodeInfo<RLike> info() {
-        return NodeInfo.create(this, RLike::new, left(), (Literal) right());
+    public String pattern() {
+        return pattern;
     }
 
     @Override
-    protected RLike replaceChildren(Expression newLeft, Expression newRight) {
-        return new RLike(location(), newLeft, (Literal) newRight);
+    protected NodeInfo<RLike> info() {
+        return NodeInfo.create(this, RLike::new, field(), pattern);
     }
 
     @Override
-    protected String asString(Expression pattern) {
-        return pattern.fold().toString();
+    protected RLike replaceChild(Expression newChild) {
+        return new RLike(location(), newChild, pattern);
     }
 }

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/expression/predicate/regex/RegexMatch.java

@@ -7,34 +7,45 @@
 package org.elasticsearch.xpack.sql.expression.predicate.regex;
 
 import org.elasticsearch.xpack.sql.expression.Expression;
-import org.elasticsearch.xpack.sql.expression.predicate.BinaryPredicate;
+import org.elasticsearch.xpack.sql.expression.function.scalar.UnaryScalarFunction;
+import org.elasticsearch.xpack.sql.expression.gen.processor.Processor;
 import org.elasticsearch.xpack.sql.expression.predicate.regex.RegexProcessor.RegexOperation;
 import org.elasticsearch.xpack.sql.tree.Location;
 import org.elasticsearch.xpack.sql.type.DataType;
 
-public abstract class RegexMatch extends BinaryPredicate<String, String, Boolean, RegexOperation> {
+public abstract class RegexMatch extends UnaryScalarFunction {
 
-    protected RegexMatch(Location location, Expression value, Expression pattern) {
-        super(location, value, pattern, RegexOperation.INSTANCE);
+    private final String pattern;
+
+    protected RegexMatch(Location location, Expression value, String pattern) {
+        super(location, value);
+        this.pattern = pattern;
     }
 
     @Override
     public DataType dataType() {
         return DataType.BOOLEAN;
     }
 
+    @Override
+    public boolean nullable() {
+        return field().nullable() && pattern != null;
+    }
+
     @Override
     public boolean foldable() {
         // right() is not directly foldable in any context but Like can fold it.
-        return left().foldable();
+        return field().foldable();
     }
 
     @Override
     public Boolean fold() {
-        Object val = left().fold();
-        val = val != null ? val.toString() : val;
-        return function().apply((String) val, asString(right()));
+        Object val = field().fold();
+        return RegexOperation.match(val, pattern);
     }
 
-    protected abstract String asString(Expression pattern);
+    @Override
+    protected Processor makeProcessor() {
+        return new RegexProcessor(pattern);
+    }
 }

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/expression/predicate/regex/RegexPipe.java

@@ -7,79 +7,71 @@
 
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.xpack.sql.SqlIllegalArgumentException;
-import org.elasticsearch.xpack.sql.expression.gen.processor.BinaryProcessor;
 import org.elasticsearch.xpack.sql.expression.gen.processor.Processor;
-import org.elasticsearch.xpack.sql.expression.predicate.PredicateBiFunction;
 
 import java.io.IOException;
 import java.util.Objects;
 import java.util.regex.Pattern;
 
-public class RegexProcessor extends BinaryProcessor {
+public class RegexProcessor implements Processor {
 
-    public static class RegexOperation implements PredicateBiFunction<String, String, Boolean> {
+    public static class RegexOperation {
 
-        public static final RegexOperation INSTANCE = new RegexOperation();
+        public static Boolean match(Object value, Pattern pattern) {
+            if (pattern == null) {
+                return Boolean.TRUE;
+            }
 
-        @Override
-        public String name() {
-            return symbol();
-        }
+            if (value == null) {
+                return null;
+            }
 
-        @Override
-        public String symbol() {
-            return "REGEX";
+            return pattern.matcher(value.toString()).matches();
         }
 
-        @Override
-        public Boolean doApply(String value, String pattern) {
-            return match(value, pattern);
-        }
+        public static Boolean match(Object value, String pattern) {
+            if (pattern == null) {
+                return Boolean.TRUE;
+            }
 
-        public static Boolean match(Object value, Object pattern) {
-            if (value == null || pattern == null) {
+            if (value == null) {
                 return null;
             }
 
-            Pattern p = Pattern.compile(pattern.toString());
-            return p.matcher(value.toString()).matches();
+            return Pattern.compile(pattern).matcher(value.toString()).matches();
         }
     }
 
     public static final String NAME = "rgx";
 
-    public RegexProcessor(Processor value, Processor pattern) {
-        super(value, pattern);
-    }
+    private Pattern pattern;
 
-    public RegexProcessor(StreamInput in) throws IOException {
-        super(in);
+    public RegexProcessor(String pattern) {
+        this.pattern = pattern != null ? Pattern.compile(pattern) : null;
     }
 
     @Override
-    protected Boolean doProcess(Object value, Object pattern) {
-        return RegexOperation.match(value, pattern);
+    public String getWriteableName() {
+        return NAME;
     }
 
-    @Override
-    protected void checkParameter(Object param) {
-        if (!(param instanceof String || param instanceof Character)) {
-            throw new SqlIllegalArgumentException("A string/char is required; received [{}]", param);
-        }
+    public RegexProcessor(StreamInput in) throws IOException {
+        this(in.readOptionalString());
     }
 
     @Override
-    public String getWriteableName() {
-        return NAME;
+    public void writeTo(StreamOutput out) throws IOException {
+        out.writeOptionalString(pattern != null ? pattern.toString() : null);
     }
 
     @Override
-    protected void doWrite(StreamOutput out) throws IOException {}
+    public Object process(Object input) {
+        return RegexOperation.match(input, pattern);
+    }
 
     @Override
     public int hashCode() {
-        return Objects.hash(left(), right());
+        return Objects.hash(pattern);
     }
 
     @Override
@@ -93,6 +85,6 @@ public boolean equals(Object obj) {
         }
 
         RegexProcessor other = (RegexProcessor) obj;
-        return Objects.equals(left(), other.left()) && Objects.equals(right(), other.right());
+        return Objects.equals(pattern, other.pattern);
     }
 }

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/expression/predicate/regex/RegexProcessor.java

@@ -232,7 +232,7 @@ public Expression visitPredicated(PredicatedContext ctx) {
                 e = new Like(loc, exp, visitPattern(pCtx.pattern()));
                 break;
             case SqlBaseParser.RLIKE:
-                e = new RLike(loc, exp, new Literal(source(pCtx.regex), string(pCtx.regex), DataType.KEYWORD));
+                e = new RLike(loc, exp, string(pCtx.regex));
                 break;
             case SqlBaseParser.NULL:
                 // shortcut to avoid double negation later on (since there's no IsNull (missing in ES is a negated exists))
@@ -301,7 +301,7 @@ public LikePattern visitPattern(PatternContext ctx) {
             }
         }
 
-        return new LikePattern(source(ctx), pattern, escape);
+        return new LikePattern(pattern, escape);
     }