supporting/fixing unique inside sql function such as count eg - SELECT count(UNIQUE col2) FROM mytable (#1184)

Co-authored-by: Adhikesavan <radhikesavan@paypal.com>

Author: sur5an

src/main/java/net/sf/jsqlparser/expression/AnalyticExpression.java

@@ -34,6 +34,7 @@ public class AnalyticExpression extends ASTNodeAccessImpl implements Expression
     private KeepExpression keep = null;
     private AnalyticType type = AnalyticType.OVER;
     private boolean distinct = false;
+    private boolean unique = false;
     private boolean ignoreNulls = false;
     private Expression filterExpression = null;
     private WindowElement windowElement = null;
@@ -45,6 +46,7 @@ public AnalyticExpression(Function function) {
         name = function.getName();
         allColumns = function.isAllColumns();
         distinct = function.isDistinct();
+        unique = function.isUnique();
 
         ExpressionList list = function.getParameters();
         if (list != null) {
@@ -157,6 +159,14 @@ public void setDistinct(boolean distinct) {
         this.distinct = distinct;
     }
 
+    public boolean isUnique() {
+        return unique;
+    }
+
+    public void setUnique(boolean unique) {
+        this.unique = unique;
+    }
+
     public boolean isIgnoreNulls() {
         return ignoreNulls;
     }
@@ -284,6 +294,11 @@ public AnalyticExpression withDistinct(boolean distinct) {
         return this;
     }
 
+    public AnalyticExpression withUnique(boolean unique) {
+        this.setUnique(unique);
+        return this;
+    }
+
     public AnalyticExpression withIgnoreNulls(boolean ignoreNulls) {
         this.setIgnoreNulls(ignoreNulls);
         return this;

src/main/java/net/sf/jsqlparser/expression/Function.java

@@ -27,6 +27,7 @@ public class Function extends ASTNodeAccessImpl implements Expression {
     private NamedExpressionList namedParameters;
     private boolean allColumns = false;
     private boolean distinct = false;
+    private boolean unique = false;
     private boolean isEscaped = false;
     private Expression attribute;
     private String attributeName;
@@ -89,6 +90,19 @@ public void setDistinct(boolean b) {
         distinct = b;
     }
 
+    /**
+     * true if the function is "unique"
+     *
+     * @return true if the function is "unique"
+     */
+    public boolean isUnique() {
+        return unique;
+    }
+
+    public void setUnique(boolean b) {
+        unique = b;
+    }
+
     /**
      * The list of parameters of the function (if any, else null) If the parameter is "*",
      * allColumns is set to true
@@ -164,6 +178,8 @@ public String toString() {
                 b.append("(");
                 if (isDistinct()) {
                     b.append("DISTINCT ");
+                } else if (isUnique()) {
+                    b.append("UNIQUE ");
                 }
                 if (isAllColumns()) {
                     b.append("ALL ");
@@ -251,6 +267,11 @@ public Function withDistinct(boolean distinct) {
         return this;
     }
 
+    public Function withUnique(boolean unique) {
+        this.setUnique(unique);
+        return this;
+    }
+
     public List<OrderByElement> getOrderByElements() {
         return orderByElements;
     }

src/main/java/net/sf/jsqlparser/util/deparser/ExpressionDeParser.java

@@ -493,6 +493,9 @@ public void visit(Function function) {
                 buffer.append("DISTINCT ");
             } else if (function.isAllColumns()) {
                 buffer.append("ALL ");
+            } else if (function.isUnique()) {
+                useBracketsInExprList = false;
+                buffer.append("(UNIQUE ");
             }
             if (function.getNamedParameters() != null) {
                 visit(function.getNamedParameters());
@@ -704,6 +707,9 @@ public void visit(AnalyticExpression aexpr) {
         if (aexpr.isDistinct()) {
             buffer.append("DISTINCT ");
         }
+        if (aexpr.isUnique()) {
+            buffer.append("UNIQUE ");
+        }
         if (expression != null) {
             expression.accept(this);
             if (offset != null) {

src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt

@@ -3874,7 +3874,7 @@ Function InternalFunction(Function retval) :
 {
     funcName = RelObjectNameList()
 
-    "(" [ [ LOOKAHEAD(2)(<K_DISTINCT> { retval.setDistinct(true); } | <K_ALL> { retval.setAllColumns(true); }) ]
+    "(" [ [ LOOKAHEAD(2)(<K_DISTINCT> { retval.setDistinct(true); } | <K_ALL> { retval.setAllColumns(true); } | <K_UNIQUE> { retval.setUnique(true); }) ]
         ( LOOKAHEAD(4)
             "*" { retval.setAllColumns(true); }
             |

src/test/java/net/sf/jsqlparser/statement/select/SelectTest.java

@@ -1590,6 +1590,11 @@ public void testCount2() throws JSQLParserException {
         assertSqlCanBeParsedAndDeparsed("SELECT count(ALL col1 + col2) FROM mytable");
     }
 
+    @Test
+    public void testCount3() throws JSQLParserException {
+        assertSqlCanBeParsedAndDeparsed("SELECT count(UNIQUE col) FROM mytable");
+    }
+
     @Test
     public void testMysqlQuote() throws JSQLParserException {
         String statement = "SELECT `a.OWNERLASTNAME`, `OWNERFIRSTNAME` " + "FROM `ANTIQUEOWNERS` AS a, ANTIQUES AS b "