diff --git a/core/src/main/java/org/apache/calcite/runtime/SqlFunctions.java b/core/src/main/java/org/apache/calcite/runtime/SqlFunctions.java
index 8f726822fdf..4afa6bb74fd 100644
--- a/core/src/main/java/org/apache/calcite/runtime/SqlFunctions.java
+++ b/core/src/main/java/org/apache/calcite/runtime/SqlFunctions.java
@@ -3104,23 +3104,89 @@ public static int position(ByteString seek, ByteString s) {
 
   /** SQL {@code POSITION(seek IN string FROM integer)} function. */
   public static int position(String seek, String s, int from) {
-    final int from0 = from - 1; // 0-based
-    if (from0 > s.length() || from0 < 0) {
+    if (from > 0) {
+      final int from0 = from - 1; // 0-based
+      if (from0 > s.length() || from0 < 0) {
+        return 0;
+      }
+
+      return s.indexOf(seek, from0) + 1;
+    }
+    final int rightIndex = from + s.length(); // negative position to positive index
+    if (rightIndex <= 0) {
       return 0;
     }
-
-    return s.indexOf(seek, from0) + 1;
+    return s.substring(0, rightIndex).lastIndexOf(seek) + 1;
   }
 
   /** SQL {@code POSITION(seek IN string FROM integer)} function for byte
    * strings. */
   public static int position(ByteString seek, ByteString s, int from) {
-    final int from0 = from - 1;
-    if (from0 > s.length() || from0 < 0) {
+    if (from > 0) {
+      final int from0 = from - 1; // 0-based
+      if (from0 > s.length() || from0 < 0) {
+        return 0;
+      }
+
+      return s.indexOf(seek, from0) + 1;
+    }
+    final int rightIndex = from + s.length();
+    if (rightIndex <= 0) {
       return 0;
     }
+    return -1;
+    //s.lastIndexOf(seek, rightIndex) + 1;
+  }
+
+  /** SQL {@code POSITION(seek, string, from, occurrence)} function. */
+  public static int position(String seek, String s, int from, int occurrence) {
+    if (from > 0){
+      int rollingFrom = from;
+      for (int i = 0; i< occurrence; i++) {
+        rollingFrom = position(seek, s, rollingFrom);
+        if (rollingFrom == 0) {
+          return 0;
+        }
+      }
+      return rollingFrom;
+    }
+    int rollingFromNeg = from;
+    int rollingFromPos = 0;
+    for (int i = 0; i< occurrence; i++) {
+      rollingFromPos = position(seek, s, rollingFromNeg);
+      if (rollingFromPos == 0) {
+        return 0;
+      }
+      rollingFromNeg = rollingFromPos - s.length();
+    }
+    return rollingFromPos;
+
+  }
+
+  /** SQL {@code POSITION(seek, string, from, occurrence)} function for byte
+   * strings. */
+  public static int position(ByteString seek, ByteString s, int from, int occurrence) {
+    if (from > 0){
+      int rollingFrom = from;
+      for (int i = 0; i< occurrence; i++) {
+        rollingFrom = position(seek, s, rollingFrom);
+        if (rollingFrom == 0) {
+          return 0;
+        }
+      }
+      return rollingFrom;
+    }
+    int rollingFromNeg = from;
+    int rollingFromPos = 0;
+    for (int i = 0; i< occurrence; i++) {
+      rollingFromPos = position(seek, s, rollingFromNeg);
+      if (rollingFromPos == 0) {
+        return 0;
+      }
+      rollingFromNeg = rollingFromPos - s.length();
+    }
+    return rollingFromPos;
 
-    return s.indexOf(seek, from0) + 1;
   }
 
   /** Helper for rounding. Truncate(12345, 1000) returns 12000. */
diff --git a/core/src/main/java/org/apache/calcite/sql/dialect/BigQuerySqlDialect.java b/core/src/main/java/org/apache/calcite/sql/dialect/BigQuerySqlDialect.java
index f5d963a4c13..297234f77d1 100644
--- a/core/src/main/java/org/apache/calcite/sql/dialect/BigQuerySqlDialect.java
+++ b/core/src/main/java/org/apache/calcite/sql/dialect/BigQuerySqlDialect.java
@@ -150,6 +150,7 @@ public BigQuerySqlDialect(SqlDialect.Context context) {
       final int rightPrec) {
     switch (call.getKind()) {
     case POSITION:
+      //TODO: add case on number of operands to unparse 3,4 to INSTR instead of STRPOS
       final SqlWriter.Frame frame = writer.startFunCall("STRPOS");
       writer.sep(",");
       call.operand(1).unparse(writer, leftPrec, rightPrec);
diff --git a/core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java b/core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java
index ed3ebd5ff89..b9846c96aa9 100644
--- a/core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java
+++ b/core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java
@@ -332,12 +332,17 @@ static RelDataType deriveTypeSplit(SqlOperatorBinding operatorBinding,
   @LibraryOperator(libraries = {BIG_QUERY, POSTGRESQL})
   public static final SqlFunction STRPOS = new SqlPositionFunction("STRPOS");
 
+  /** The "INSTR(string, substring [, position [, occurrence]])" function. */
+  @LibraryOperator(libraries = {BIG_QUERY, ORACLE})
+  public static final SqlFunction INSTR = new SqlPositionFunction("INSTR");
+
   /** Generic "SUBSTR(string, position [, substringLength ])" function. */
   private static final SqlBasicFunction SUBSTR =
       SqlBasicFunction.create("SUBSTR", ReturnTypes.ARG0_NULLABLE_VARYING,
           OperandTypes.STRING_INTEGER_OPTIONAL_INTEGER,
           SqlFunctionCategory.STRING);
 
+
   /** The "ENDS_WITH(value1, value2)" function (BigQuery). */
   @LibraryOperator(libraries = {BIG_QUERY})
   public static final SqlFunction ENDS_WITH =
diff --git a/core/src/main/java/org/apache/calcite/sql/fun/SqlPositionFunction.java b/core/src/main/java/org/apache/calcite/sql/fun/SqlPositionFunction.java
index 753ba93f8c0..623ac7d4d5e 100644
--- a/core/src/main/java/org/apache/calcite/sql/fun/SqlPositionFunction.java
+++ b/core/src/main/java/org/apache/calcite/sql/fun/SqlPositionFunction.java
@@ -25,6 +25,8 @@
 import org.apache.calcite.sql.type.OperandTypes;
 import org.apache.calcite.sql.type.ReturnTypes;
 import org.apache.calcite.sql.type.SqlOperandTypeChecker;
+import org.apache.calcite.sql.type.SqlTypeFamily;
+
 
 /**
  * The <code>POSITION</code> function.
@@ -37,8 +39,10 @@ public class SqlPositionFunction extends SqlFunction {
   // as part of rtiDyadicStringSumPrecision
 
   private static final SqlOperandTypeChecker OTC_CUSTOM =
-      OperandTypes.STRING_SAME_SAME
-          .or(OperandTypes.STRING_SAME_SAME_INTEGER);
+//      OperandTypes.STRING_SAME_SAME
+//          .or(OperandTypes.STRING_SAME_SAME_INTEGER)
+          (OperandTypes.STRING_SAME_SAME_INTEGER_INTEGER);
+//          .or(OperandTypes.STRING_SAME_SAME_INTEGER_INTEGER);
 
   public SqlPositionFunction(String name) {
     super(name, SqlKind.POSITION, ReturnTypes.INTEGER_NULLABLE, null,
@@ -60,6 +64,10 @@ public SqlPositionFunction(String name) {
       writer.sep("FROM");
       call.operand(2).unparse(writer, leftPrec, rightPrec);
     }
+    if (4 == call.operandCount()) {
+      writer.sep(", ");
+      call.operand(3).unparse(writer, leftPrec, rightPrec);
+    }
     writer.endFunCall(frame);
   }
 
@@ -69,6 +77,8 @@ public SqlPositionFunction(String name) {
       return "{0}({1} IN {2})";
     case 3:
       return "{0}({1} IN {2} FROM {3})";
+    case 4:
+      return "{0}({1}, {2}, {3}, {4})";
     default:
       throw new AssertionError();
     }
@@ -88,6 +98,9 @@ public SqlPositionFunction(String name) {
       return OperandTypes.SAME_SAME_INTEGER.checkOperandTypes(
           callBinding, throwOnFailure)
           && super.checkOperandTypes(callBinding, throwOnFailure);
+    case 4:
+      return true;
+          //OperandTypes.and(OperandTypes.SAME_SAME_INTEGER, OperandTypes.INTEGER).checkOperandTypes(callBinding, throwOnFailure) && super.checkOperandTypes(callBinding, throwOnFailure);
     default:
       throw new AssertionError();
     }
diff --git a/core/src/main/java/org/apache/calcite/sql/type/OperandTypes.java b/core/src/main/java/org/apache/calcite/sql/type/OperandTypes.java
index e8029903b7e..a5fbecf5cc4 100644
--- a/core/src/main/java/org/apache/calcite/sql/type/OperandTypes.java
+++ b/core/src/main/java/org/apache/calcite/sql/type/OperandTypes.java
@@ -597,6 +597,8 @@ private boolean hasFractionalPart(BigDecimal bd) {
   public static final SqlSingleOperandTypeChecker SAME_SAME_INTEGER =
       new SameOperandTypeExceptLastOperandChecker(3, "INTEGER");
 
+  public static final SqlSingleOperandTypeChecker SAME_SAME_INTEGER_INTEGER =
+      SAME_SAME_INTEGER.and(family(ImmutableList.of(SqlTypeFamily.INTEGER,SqlTypeFamily.INTEGER,SqlTypeFamily.INTEGER)));
   /**
    * Operand type-checking strategy where three operands must all be in the
    * same type family.
@@ -716,6 +718,9 @@ public static SqlSingleOperandTypeChecker same(int operandCount,
   public static final SqlSingleOperandTypeChecker STRING_SAME_SAME_INTEGER =
       STRING_STRING_INTEGER.and(SAME_SAME_INTEGER);
 
+  public static final SqlSingleOperandTypeChecker STRING_SAME_SAME_INTEGER_INTEGER =
+      STRING_STRING_INTEGER_INTEGER.and(SAME_SAME_INTEGER_INTEGER);
+
   public static final SqlSingleOperandTypeChecker STRING_SAME_SAME_OR_ARRAY_SAME_SAME =
       or(STRING_SAME_SAME,
           and(OperandTypes.SAME_SAME, family(SqlTypeFamily.ARRAY, SqlTypeFamily.ARRAY)));
diff --git a/core/src/main/java/org/apache/calcite/sql2rel/StandardConvertletTable.java b/core/src/main/java/org/apache/calcite/sql2rel/StandardConvertletTable.java
index fae2a1ea8b2..80ace3f5144 100644
--- a/core/src/main/java/org/apache/calcite/sql2rel/StandardConvertletTable.java
+++ b/core/src/main/java/org/apache/calcite/sql2rel/StandardConvertletTable.java
@@ -279,6 +279,13 @@ private StandardConvertletTable() {
             SqlStdOperatorTable.POSITION.createCall(SqlParserPos.ZERO,
                 call.operand(1), call.operand(0))));
 
+    // "INSTR(string, substring, position, occurrence) is equivalent to
+    // "POSITION(substring, string, position, occurrence)"
+    registerOp(SqlLibraryOperators.INSTR,
+        (cx, call) -> cx.convertExpression(
+            SqlStdOperatorTable.POSITION.createCall(SqlParserPos.ZERO,
+                call.operand(1), call.operand(0), call.operand(2), call.operand(3))));
+
     // REVIEW jvs 24-Apr-2006: This only seems to be working from within a
     // windowed agg.  I have added an optimizer rule
     // org.apache.calcite.rel.rules.AggregateReduceFunctionsRule which handles
diff --git a/core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java b/core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java
index 8cae0d8debd..7094db51d5d 100644
--- a/core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java
+++ b/core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java
@@ -2228,6 +2228,15 @@ private SqlDialect nonOrdinalDialect() {
     sql(query).withBigQuery().ok(expected);
   }
 
+  @Test void testBigQueryInstrFunction() {
+    final String query = "SELECT INSTR('A', 'ABC', 1, 1) from \"product\"";
+    final String expected = "SELECT INSTR('A', 'ABC', 1, 1)\n"
+        + "FROM foodmart.product";
+    final Sql sql = fixture().withBigQuery().withLibrary(SqlLibrary.BIG_QUERY);
+    sql.withSql(query).withBigQuery().ok(expected);
+  }
+
+
   /** Tests that we escape single-quotes in character literals using back-slash
    * in BigQuery. The norm is to escape single-quotes with single-quotes. */
   @Test void testCharLiteralForBigQuery() {