Add support for DATEADD, DATEDIFF, and related functions; normalize parameters in function calls

aasimkhan30 · aasimkhan30 · commit f0dfd2ef9634 · 2026-04-21T11:19:56.000-07:00
diff --git a/SqlScriptDom/Parser/TSql/CodeGenerationSupporter.cs b/SqlScriptDom/Parser/TSql/CodeGenerationSupporter.cs
@@ -293,13 +293,20 @@ internal static class CodeGenerationSupporter
         internal const string DataRetention = "DATA_RETENTION";
         internal const string DataSource = "DATA_SOURCE";
         internal const string Date = "DATE";
+        internal const string DateAdd = "DATEADD";
+        internal const string DateBucket = "DATE_BUCKET";
         internal const string DateCorrelationOptimization = "DATE_CORRELATION_OPTIMIZATION";
+        internal const string DateDiff = "DATEDIFF";
+        internal const string DateDiffBig = "DATEDIFF_BIG";
         internal const string DateFirst = "DATEFIRST";
         internal const string DateFormat = "DATEFORMAT";
         internal const string DateFormat2 = "DATE_FORMAT";
+        internal const string DateName = "DATENAME";
+        internal const string DatePart = "DATEPART";
         internal const string DateTime = "DATETIME";
         internal const string DateTime2 = "DATETIME2";
         internal const string DateTimeOffset = "DATETIMEOFFSET";
+        internal const string DateTrunc = "DATETRUNC";
         internal const string Deterministic = "DETERMINISTIC";
         internal const string DboOnly = "DBO_ONLY";
         internal const string DbChaining = "DB_CHAINING";
diff --git a/SqlScriptDom/Parser/TSql/TSql100.g b/SqlScriptDom/Parser/TSql/TSql100.g
@@ -20874,6 +20874,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql110.g b/SqlScriptDom/Parser/TSql/TSql110.g
@@ -23849,6 +23849,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql120.g b/SqlScriptDom/Parser/TSql/TSql120.g
@@ -24598,6 +24598,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql130.g b/SqlScriptDom/Parser/TSql/TSql130.g
@@ -29420,6 +29420,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql140.g b/SqlScriptDom/Parser/TSql/TSql140.g
@@ -30237,6 +30237,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql150.g b/SqlScriptDom/Parser/TSql/TSql150.g
@@ -31390,6 +31390,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql160.g b/SqlScriptDom/Parser/TSql/TSql160.g
@@ -32215,6 +32215,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql170.g b/SqlScriptDom/Parser/TSql/TSql170.g
@@ -33343,6 +33343,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql180.g b/SqlScriptDom/Parser/TSql/TSql180.g
@@ -33343,6 +33343,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSql80.g b/SqlScriptDom/Parser/TSql/TSql80.g
@@ -9103,6 +9103,9 @@ identifierBuiltInFunctionCallDefaultParams [FunctionCall vParent]
 }
     :
         expressionList[vParent, vParent.Parameters]
+        {
+            NormalizeDatePartFunctionFirstParameter(vParent);
+        }
     |
         vColumn=starColumnReferenceExpression
         {
diff --git a/SqlScriptDom/Parser/TSql/TSql80ParserBaseInternal.cs b/SqlScriptDom/Parser/TSql/TSql80ParserBaseInternal.cs
@@ -1979,6 +1979,51 @@ protected void PutIdentifiersIntoFunctionCall(FunctionCall functionCall, MultiPa
             }
         }
 
+        protected void NormalizeDatePartFunctionFirstParameter(FunctionCall functionCall)
+        {
+            if (functionCall == null ||
+                functionCall.FunctionName == null ||
+                String.IsNullOrEmpty(functionCall.FunctionName.Value) ||
+                functionCall.Parameters == null ||
+                functionCall.Parameters.Count == 0 ||
+                !IsDatePartFunction(functionCall.FunctionName.Value))
+            {
+                return;
+            }
+
+            ColumnReferenceExpression columnReference = functionCall.Parameters[0] as ColumnReferenceExpression;
+            if (columnReference == null ||
+                columnReference.MultiPartIdentifier == null ||
+                columnReference.MultiPartIdentifier.Count != 1)
+            {
+                return;
+            }
+
+            Identifier identifier = columnReference.MultiPartIdentifier[0];
+            IdentifierLiteral literal = FragmentFactory.CreateFragment<IdentifierLiteral>();
+            literal.Value = identifier.Value;
+            literal.QuoteType = identifier.QuoteType;
+            literal.UpdateTokenInfo(columnReference);
+            functionCall.Parameters[0] = literal;
+        }
+
+        private static bool IsDatePartFunction(string functionName)
+        {
+            switch (functionName.ToUpper(CultureInfo.InvariantCulture))
+            {
+                case CodeGenerationSupporter.DateAdd:
+                case CodeGenerationSupporter.DateBucket:
+                case CodeGenerationSupporter.DateDiff:
+                case CodeGenerationSupporter.DateDiffBig:
+                case CodeGenerationSupporter.DateName:
+                case CodeGenerationSupporter.DatePart:
+                case CodeGenerationSupporter.DateTrunc:
+                    return true;
+                default:
+                    return false;
+            }
+        }
+
         protected void VerifyColumnDataType(ColumnDefinition column)
         {
             // If the scalarDataType is not parsed, the ColumnIdentifier has to be a timestamp.
@@ -2426,4 +2471,4 @@ protected static TSqlParseErrorException GetUnexpectedTokenErrorException(Identi
 
         #endregion
     }
-}
+}
diff --git a/SqlScriptDom/Parser/TSql/TSql90.g b/SqlScriptDom/Parser/TSql/TSql90.g
@@ -16550,6 +16550,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/SqlScriptDom/Parser/TSql/TSqlFabricDW.g b/SqlScriptDom/Parser/TSql/TSqlFabricDW.g
@@ -32381,6 +32381,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]
     :
         (
             expressionList[vParent, vParent.Parameters]
+            {
+                NormalizeDatePartFunctionFirstParameter(vParent);
+            }
         |
             vColumn=starColumnReferenceExpression
             {
diff --git a/Test/SqlDom/Only160SyntaxTests.cs b/Test/SqlDom/Only160SyntaxTests.cs
@@ -154,6 +154,37 @@ public void TSql160Azure_SyntaxIn160ParserTest()
             }
         }
 
+        [TestMethod]
+        [Priority(0)]
+        [SqlStudioTestCategory(Category.UnitTest)]
+        public void DatePartFunctionParametersAreIdentifierLiteralsTest()
+        {
+            TSql160Parser parser = new TSql160Parser(true);
+
+            VerifyDatePartParameter(parser, "SELECT DATEDIFF(mm, ColA, ColB) FROM my_table;", "mm");
+            VerifyDatePartParameter(parser, "SELECT DATEADD(day, 1, ColA) FROM my_table;", "day");
+            VerifyDatePartParameter(parser, "SELECT DATEDIFF_BIG(second, ColA, ColB) FROM my_table;", "second");
+            VerifyDatePartParameter(parser, "SELECT DATENAME(month, ColA) FROM my_table;", "month");
+            VerifyDatePartParameter(parser, "SELECT DATEPART(wk, ColA) FROM my_table;", "wk");
+            VerifyDatePartParameter(parser, "SELECT DATE_BUCKET(WEEK, 10, ColA) FROM my_table;", "WEEK");
+            VerifyDatePartParameter(parser, "SELECT DATETRUNC(year, ColA) FROM my_table;", "year");
+        }
+
+        private static void VerifyDatePartParameter(TSqlParser parser, string sql, string expectedDatePart)
+        {
+            TSqlFragment fragment = parser.Parse(new System.IO.StringReader(sql), out System.Collections.Generic.IList<ParseError> errors);
+
+            Assert.AreEqual(0, errors.Count, sql);
+            TSqlScript script = (TSqlScript)fragment;
+            SelectStatement select = (SelectStatement)script.Batches[0].Statements[0];
+            QuerySpecification query = (QuerySpecification)select.QueryExpression;
+            SelectScalarExpression selectExpression = (SelectScalarExpression)query.SelectElements[0];
+            FunctionCall functionCall = (FunctionCall)selectExpression.Expression;
+
+            Assert.IsInstanceOfType(functionCall.Parameters[0], typeof(IdentifierLiteral), sql);
+            Assert.AreEqual(expectedDatePart, ((IdentifierLiteral)functionCall.Parameters[0]).Value, sql);
+        }
+
         [TestMethod]
         [Priority(0)]
         [SqlStudioTestCategory(Category.UnitTest)]

Original file line number	Diff line number	Diff line change
`@@ -20874,6 +20874,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]`
`20874`	`20874`	`:`
`20875`	`20875`	`(`
`20876`	`20876`	`expressionList[vParent, vParent.Parameters]`
	`20877`	`+ {`
	`20878`	`+ NormalizeDatePartFunctionFirstParameter(vParent);`
	`20879`	`+ }`
`20877`	`20880`	`\|`
`20878`	`20881`	`vColumn=starColumnReferenceExpression`
`20879`	`20882`	`{`
Original file line number	Diff line number	Diff line change
`@@ -23849,6 +23849,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]`
`23849`	`23849`	`:`
`23850`	`23850`	`(`
`23851`	`23851`	`expressionList[vParent, vParent.Parameters]`
	`23852`	`+ {`
	`23853`	`+ NormalizeDatePartFunctionFirstParameter(vParent);`
	`23854`	`+ }`
`23852`	`23855`	`\|`
`23853`	`23856`	`vColumn=starColumnReferenceExpression`
`23854`	`23857`	`{`
Original file line number	Diff line number	Diff line change
`@@ -24598,6 +24598,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]`
`24598`	`24598`	`:`
`24599`	`24599`	`(`
`24600`	`24600`	`expressionList[vParent, vParent.Parameters]`
	`24601`	`+ {`
	`24602`	`+ NormalizeDatePartFunctionFirstParameter(vParent);`
	`24603`	`+ }`
`24601`	`24604`	`\|`
`24602`	`24605`	`vColumn=starColumnReferenceExpression`
`24603`	`24606`	`{`
Original file line number	Diff line number	Diff line change
`@@ -29420,6 +29420,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]`
`29420`	`29420`	`:`
`29421`	`29421`	`(`
`29422`	`29422`	`expressionList[vParent, vParent.Parameters]`
	`29423`	`+ {`
	`29424`	`+ NormalizeDatePartFunctionFirstParameter(vParent);`
	`29425`	`+ }`
`29423`	`29426`	`\|`
`29424`	`29427`	`vColumn=starColumnReferenceExpression`
`29425`	`29428`	`{`
Original file line number	Diff line number	Diff line change
`@@ -30237,6 +30237,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]`
`30237`	`30237`	`:`
`30238`	`30238`	`(`
`30239`	`30239`	`expressionList[vParent, vParent.Parameters]`
	`30240`	`+ {`
	`30241`	`+ NormalizeDatePartFunctionFirstParameter(vParent);`
	`30242`	`+ }`
`30240`	`30243`	`\|`
`30241`	`30244`	`vColumn=starColumnReferenceExpression`
`30242`	`30245`	`{`
Original file line number	Diff line number	Diff line change
`@@ -31390,6 +31390,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]`
`31390`	`31390`	`:`
`31391`	`31391`	`(`
`31392`	`31392`	`expressionList[vParent, vParent.Parameters]`
	`31393`	`+ {`
	`31394`	`+ NormalizeDatePartFunctionFirstParameter(vParent);`
	`31395`	`+ }`
`31393`	`31396`	`\|`
`31394`	`31397`	`vColumn=starColumnReferenceExpression`
`31395`	`31398`	`{`
Original file line number	Diff line number	Diff line change
`@@ -32215,6 +32215,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]`
`32215`	`32215`	`:`
`32216`	`32216`	`(`
`32217`	`32217`	`expressionList[vParent, vParent.Parameters]`
	`32218`	`+ {`
	`32219`	`+ NormalizeDatePartFunctionFirstParameter(vParent);`
	`32220`	`+ }`
`32218`	`32221`	`\|`
`32219`	`32222`	`vColumn=starColumnReferenceExpression`
`32220`	`32223`	`{`
Original file line number	Diff line number	Diff line change
`@@ -33343,6 +33343,9 @@ regularBuiltInFunctionCall [FunctionCall vParent]`
`33343`	`33343`	`:`
`33344`	`33344`	`(`
`33345`	`33345`	`expressionList[vParent, vParent.Parameters]`
	`33346`	`+ {`
	`33347`	`+ NormalizeDatePartFunctionFirstParameter(vParent);`
	`33348`	`+ }`
`33346`	`33349`	`\|`
`33347`	`33350`	`vColumn=starColumnReferenceExpression`
`33348`	`33351`	`{`