diff --git a/src/firefly/html/test/images/gator-expected.jpg b/src/firefly/html/test/images/gator-expected.jpg
index 5554f52975..a696ebd513 100644
Binary files a/src/firefly/html/test/images/gator-expected.jpg and b/src/firefly/html/test/images/gator-expected.jpg differ
diff --git a/src/firefly/html/test/tests-main.html b/src/firefly/html/test/tests-main.html
index 912a17da26..6898982a4a 100644
--- a/src/firefly/html/test/tests-main.html
+++ b/src/firefly/html/test/tests-main.html
@@ -18,10 +18,10 @@
 
 <template title="IRSA Gator Table" class="tpl" >
     <div id="expected" style="position: relative" >
-        <img style="position: absolute; right: 2px; width: 275px" src="./images/gator-expected.jpg"/>
+        <img style="position: absolute; left: 2px" src="./images/gator-expected.jpg"/>
         <div class="source-code indent-3" style="position: absolute; bottom: 0; left: 0">
+            - toolbars matches above
             - widgets loaded
-            - toolbars match
         </div>
     </div>
     <div id="actual" class="flow-h">
diff --git a/src/firefly/java/edu/caltech/ipac/firefly/server/db/BaseDbAdapter.java b/src/firefly/java/edu/caltech/ipac/firefly/server/db/BaseDbAdapter.java
index d12fddd8df..1193d88ad5 100644
--- a/src/firefly/java/edu/caltech/ipac/firefly/server/db/BaseDbAdapter.java
+++ b/src/firefly/java/edu/caltech/ipac/firefly/server/db/BaseDbAdapter.java
@@ -9,7 +9,6 @@
 import edu.caltech.ipac.firefly.server.util.Logger;
 import edu.caltech.ipac.table.DataType;
 import edu.caltech.ipac.util.StringUtils;
-import org.apache.xpath.operations.Bool;
 
 import java.io.File;
 import java.util.ArrayList;
@@ -19,6 +18,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
 import static edu.caltech.ipac.firefly.data.TableServerRequest.INCL_COLUMNS;
@@ -134,10 +134,14 @@ public String wherePart(TableServerRequest treq) {
         if (treq.getFilters() != null && treq.getFilters().size() > 0) {
             where = "";
             for (String cond :treq.getFilters()) {
-                if (cond.matches("(?i).* LIKE .*(\\\\_|\\\\%|\\\\\\\\).*")) {       // search for LIKE w/  \_, \%, or \\ in the condition.
+                if (cond.matches("(?i).* LIKE .*(\\\\_|\\\\%|\\\\\\\\).*")) {       // search for LIKE with  \_, \%, or \\ in the condition.
                     // for LIKE, to search for '%', '\' or '_' itself, an escape character must also be specified using the ESCAPE clause
                     cond += " ESCAPE '\\'";
                 }
+                String[] parts = StringUtils.groupMatch("(.+) IN (.+)", cond, Pattern.CASE_INSENSITIVE);
+                if (parts != null && cond.contains(NULL_TOKEN)) {
+                    cond = String.format("%s OR %s IS NULL", cond.replace(NULL_TOKEN, NULL_TOKEN.substring(1)), parts[0]);
+                }
                 if (where.length() > 0) {
                     where += " and ";
                 }
diff --git a/src/firefly/java/edu/caltech/ipac/firefly/server/db/DbAdapter.java b/src/firefly/java/edu/caltech/ipac/firefly/server/db/DbAdapter.java
index 00a81e69e6..dff21f302a 100644
--- a/src/firefly/java/edu/caltech/ipac/firefly/server/db/DbAdapter.java
+++ b/src/firefly/java/edu/caltech/ipac/firefly/server/db/DbAdapter.java
@@ -24,6 +24,7 @@ public interface DbAdapter {
     String HSQL = "hsql";
 
     String MAIN_DB_TBL = "DATA";
+    String NULL_TOKEN = "%NULL";
 
     /*
       CLEAN UP POLICY:
diff --git a/src/firefly/java/edu/caltech/ipac/firefly/server/db/EmbeddedDbUtil.java b/src/firefly/java/edu/caltech/ipac/firefly/server/db/EmbeddedDbUtil.java
index 42e878258f..a2f23f0d23 100644
--- a/src/firefly/java/edu/caltech/ipac/firefly/server/db/EmbeddedDbUtil.java
+++ b/src/firefly/java/edu/caltech/ipac/firefly/server/db/EmbeddedDbUtil.java
@@ -433,7 +433,7 @@ private static int dbToDD(DataGroup dg, ResultSet rs) {
 
                 applyIfNotEmpty(rs.getString("label"), dtype::setLabel);
                 applyIfNotEmpty(rs.getString("units"), dtype::setUnits);
-                applyIfNotEmpty(rs.getString("null_str"), dtype::setNullString);
+                dtype.setNullString(rs.getString("null_str"));
                 applyIfNotEmpty(rs.getString("format"), dtype::setFormat);
                 applyIfNotEmpty(rs.getString("fmtDisp"), dtype::setFmtDisp);
                 applyIfNotEmpty(rs.getInt("width"), dtype::setWidth);
diff --git a/src/firefly/java/edu/caltech/ipac/firefly/server/query/AsyncSearchProcessor.java b/src/firefly/java/edu/caltech/ipac/firefly/server/query/AsyncSearchProcessor.java
index 3206414c94..21cc6e7614 100644
--- a/src/firefly/java/edu/caltech/ipac/firefly/server/query/AsyncSearchProcessor.java
+++ b/src/firefly/java/edu/caltech/ipac/firefly/server/query/AsyncSearchProcessor.java
@@ -33,6 +33,7 @@ public DataGroup fetchDataGroup(TableServerRequest req) throws DataAccessExcepti
                     case COMPLETED:
                         return asyncJob.getDataGroup();
                     case ERROR:
+                    case UNKNOWN:
                         throw new DataAccessException(asyncJob.getErrorMsg());
                     case ABORTED:
                         throw new DataAccessException("Query aborted");
diff --git a/src/firefly/java/edu/caltech/ipac/firefly/server/query/EmbeddedDbProcessor.java b/src/firefly/java/edu/caltech/ipac/firefly/server/query/EmbeddedDbProcessor.java
index 2bb9822287..a6c1709fa5 100644
--- a/src/firefly/java/edu/caltech/ipac/firefly/server/query/EmbeddedDbProcessor.java
+++ b/src/firefly/java/edu/caltech/ipac/firefly/server/query/EmbeddedDbProcessor.java
@@ -55,6 +55,7 @@
 import static edu.caltech.ipac.firefly.data.table.MetaConst.HIGHLIGHTED_ROW_BY_ROWIDX;
 import static edu.caltech.ipac.firefly.server.ServerContext.SHORT_TASK_EXEC;
 import static edu.caltech.ipac.firefly.server.db.DbAdapter.MAIN_DB_TBL;
+import static edu.caltech.ipac.firefly.server.db.DbAdapter.NULL_TOKEN;
 import static edu.caltech.ipac.firefly.server.db.EmbeddedDbUtil.execRequestQuery;
 import static edu.caltech.ipac.util.StringUtils.isEmpty;
 
@@ -586,9 +587,8 @@ private static void enumeratedValuesCheck(File dbFile, DataGroupPart results, Ta
                             .queryForList(String.format("SELECT distinct \"%s\" FROM data order by 1", cname));
 
                     if (vals.size() <= MAX_COL_ENUM_COUNT) {
-                        DataType dt = results.getData().getDataDefintion(cname);
-                        String enumVals = vals.stream().map(m -> String.valueOf(m.get(cname)))       // list of map to list of string(colname)
-                                .filter(s -> !isEmpty(s) && !StringUtils.areEqual(dt.getNullString(), s))            // remove null or blank values because it's hard to handle at the column filter level
+                        String enumVals = vals.stream()
+                                .map(m -> m.get(cname) == null ? NULL_TOKEN : m.get(cname).toString())  // list of map to list of string(colname)
                                 .collect(Collectors.joining(","));                          // combine the names into comma separated string.
                         results.getData().getDataDefintion(cname).setEnumVals(enumVals);
                         // update dd table
diff --git a/src/firefly/java/edu/caltech/ipac/table/DataType.java b/src/firefly/java/edu/caltech/ipac/table/DataType.java
index 1874881ec3..95150dacf2 100644
--- a/src/firefly/java/edu/caltech/ipac/table/DataType.java
+++ b/src/firefly/java/edu/caltech/ipac/table/DataType.java
@@ -52,7 +52,7 @@ public enum Visibility {show, hide, hidden};
     private       String typeDesc;
     private       Class type;
     private       String units;
-    private       String nullString = "";
+    private       String nullString;
     private       String desc;
     private       int width;
     private       int prefWidth;
@@ -142,7 +142,7 @@ public void setUnits(String units) {
     }
 
     public String getNullString() {
-        return nullString;
+        return nullString == null ? "" : nullString;
     }
 
     public void setNullString(String nullString) {
@@ -305,9 +305,8 @@ public String getRef() {
      * @return
      */
     public String format(Object value, boolean replaceCtrl) {
-        if (value == null) {
-            return getNullString() == null ? "" : getNullString();
-        }
+        if (value == null) return getNullString();
+
         // do escaping if requested
         if (replaceCtrl && type == String.class) {
             value = replaceCtrl((String)value);
@@ -419,8 +418,7 @@ public boolean isKnownType() {
      * @return an object
      */
     public Object convertStringToData(String s) {
-        if (s == null || s.length() == 0 || s.equalsIgnoreCase("null")) return null;
-        if (nullString != null && nullString.equals(s)) return null;
+        if (s == null || getNullString().equals(s)) return null;
 
         Object retval= s;
         try {
diff --git a/src/firefly/java/edu/caltech/ipac/table/IpacTableUtil.java b/src/firefly/java/edu/caltech/ipac/table/IpacTableUtil.java
index fdf6d1475c..c85afb3fd3 100644
--- a/src/firefly/java/edu/caltech/ipac/table/IpacTableUtil.java
+++ b/src/firefly/java/edu/caltech/ipac/table/IpacTableUtil.java
@@ -246,6 +246,7 @@ public static IpacTableDef createColumnDefs(String line) {
             for (int idx = 0; idx < names.length; idx++) {
                 cname = names[idx];
                 DataType dt = new DataType(cname.trim(), null);
+                dt.setNullString("null");       // defaults to 'null'
                 cols.add(dt);
                 tableDef.setColOffsets(idx, cursor);
                 cursor += cname.length() + 1;
diff --git a/src/firefly/java/edu/caltech/ipac/util/StringUtils.java b/src/firefly/java/edu/caltech/ipac/util/StringUtils.java
index b8362a763a..b6bd5b71ab 100644
--- a/src/firefly/java/edu/caltech/ipac/util/StringUtils.java
+++ b/src/firefly/java/edu/caltech/ipac/util/StringUtils.java
@@ -74,7 +74,8 @@ public static String[] groupMatch(String regex, String val) {
      * an array of strings, otherwise null.
      * @param regex pattern to match
      * @param val   string value to match with
-     * @return
+     * @param flags Match flags, a bit mask
+     * @return return all of the matching groups as an array of strings, otherwise null.
      */
     public static String[] groupMatch(String regex, String val, int flags) {
         return groupMatch(Pattern.compile(regex, flags), val);
diff --git a/src/firefly/js/tables/FilterInfo.js b/src/firefly/js/tables/FilterInfo.js
index ba3e28324c..de276f1c53 100644
--- a/src/firefly/js/tables/FilterInfo.js
+++ b/src/firefly/js/tables/FilterInfo.js
@@ -4,7 +4,7 @@
 
 import {getColumnIdx, getColumn, isNumericType, getTblById, stripColumnNameQuotes} from './TableUtil.js';
 import {Expression} from '../util/expr/Expression.js';
-import {isUndefined, get, isArray, isEmpty} from 'lodash';
+import {isNil, get, isArray, isEmpty} from 'lodash';
 import {showInfoPopup} from '../ui/PopupUtil.jsx';
 
 const operators = /(!=|>=|<=|<|>|=| like | in | is not | is )/i;
@@ -23,6 +23,8 @@ export const FILTER_TTIPS =
 Examples:  "ra" > 12345; "color" != 'blue'; "band" IN (1,2,3)
 `;
 
+export const NULL_TOKEN = '%NULL';          // need to match DbAdapter.NULL_TOKEN
+
 /**
  * return [column_name, operator, value] triplet.
  * @param {string} input
@@ -191,7 +193,7 @@ export class FilterInfo {
 
         // remove the double quote or the single quote around cname and val (which is added in auto-correction)
         const removeQuoteAroundString = (str, quote = "'") => {
-            if (str.startsWith(quote)) {
+            if (str && str.startsWith(quote)) {
                 const reg = new RegExp('^' + quote + '(.*)' + quote + '$');
                 return str.replace(reg, '$1');
             } else {
@@ -223,7 +225,7 @@ export class FilterInfo {
             if (val.match(/^\(.*\)$/)) {
                 val = val.substring(1, val.length-1);
             }
-            val = val.split(',').map((s) => s.trim());
+            val = val.split(',').map((s) => removeQuoteAroundString(s.trim()) === NULL_TOKEN.toLowerCase() ? null : s.trim());
         }
 
         // remove single quote enclosing the string for the value of operater 'like' or char type column
@@ -236,12 +238,12 @@ export class FilterInfo {
         return (row, idx) => {
             if (!row) return false;
             let compareTo = noROWID ? idx : row[cidx];
-            if (isUndefined(compareTo)) return false;
+            compareTo = (compareTo === get(getColumn(tableModel, cname), 'nullString', '')) ? null : compareTo;     // resolve nullString
 
             if (op !== 'like' && colType.match(/^[dfil]/)) {      // int, float, double, long .. or their short form.
-                compareTo = Number(compareTo);
+                compareTo = compareTo ? Number(compareTo) : compareTo;
             } else {
-                compareTo = compareTo.toLowerCase();
+                compareTo = compareTo ? compareTo.toLowerCase() : compareTo;
             }
 
             switch (op) {
@@ -262,6 +264,10 @@ export class FilterInfo {
                     return compareTo <= val;
                 case 'in'  :
                     return val.includes(compareTo);
+                case 'is'  :
+                    return val === 'null' && isNil(compareTo);
+                case 'is not'  :
+                    return val === 'null' && !isNil(compareTo);
                 default :
                     return false;
             }
@@ -440,7 +446,7 @@ function autoCorrectCondition(v, isNumeric=false) {
     switch (op) {
         case 'like':
             if (!val.match(/^'.*'$/)) {
-                val = val.replace(/([_|%|\\])/g, '\\$1');
+                val = val.replace(/([_|%\\])/g, '\\$1');
 
                 val = encloseByQuote(encloseByQuote(val, '%'));
             }
diff --git a/src/firefly/js/tables/TableUtil.js b/src/firefly/js/tables/TableUtil.js
index 4d105ec4ed..64de25beb3 100644
--- a/src/firefly/js/tables/TableUtil.js
+++ b/src/firefly/js/tables/TableUtil.js
@@ -533,12 +533,16 @@ export function sortTableData(tableData, columns, sortInfoStr) {
     var comparator;
     if (!col.type || ['char', 'c'].includes(col.type) ) {
         comparator = (r1, r2) => {
-            const [s1, s2] = [r1[colIdx], r2[colIdx]];
+            let [s1, s2] = [r1[colIdx], r2[colIdx]];
+            s1 = s1 === '' ? '\u0002' : s1 === null ? '\u0001' : isUndefined(s1) ? '\u0000' : s1;
+            s2 = s2 === '' ? '\u0002' : s2 === null ? '\u0001' : isUndefined(s2) ? '\u0000' : s2;
             return multiplier * (s1 > s2 ? 1 : -1);
         };
     } else {
         comparator = (r1, r2) => {
-            const [v1, v2] = [r1[colIdx], r2[colIdx]];
+            let [v1, v2] = [r1[colIdx], r2[colIdx]];
+            v1 = v1 === null ? -Number.MAX_VALUE : isUndefined(v1) ? Number.NEGATIVE_INFINITY : Number(v1);
+            v2 = v2 === null ? -Number.MAX_VALUE : isUndefined(v2) ? Number.NEGATIVE_INFINITY : Number(v2);
             return multiplier * (Number(v1) - Number(v2));
         };
     }
@@ -895,8 +899,13 @@ export function tableDetailsView(tbl_id, highlightedRow, details_tbl_id) {
  */
 export function calcColumnWidths(columns, dataAry) {
     return columns.map( (cv, idx) => {
+
+        let width = cv.prefWidth || cv.width;
+        if (width) {
+            return width;
+        }
         const cname = cv.label || cv.name;
-        var width = Math.max(cname.length, get(cv, 'units.length', 0),  get(cv, 'type.length', 0));
+        width = Math.max(cname.length, get(cv, 'units.length', 0),  get(cv, 'type.length', 0));
         width = dataAry.reduce( (maxWidth, row) => {
             return Math.max(maxWidth, get(row, [idx, 'length'], 0));
         }, width);  // max width of data
diff --git a/src/firefly/js/tables/__tests__/FilterInfo-test.js b/src/firefly/js/tables/__tests__/FilterInfo-test.js
new file mode 100644
index 0000000000..1043f58712
--- /dev/null
+++ b/src/firefly/js/tables/__tests__/FilterInfo-test.js
@@ -0,0 +1,47 @@
+
+import * as TblUtil from '../TableUtil.js';         // used for named import
+import {FilterInfo} from '../FilterInfo.js';
+
+describe('FilterInfo', () => {
+
+    test('autoCorrectConditions: string columns', () => {
+
+        /*
+        *  This test is a little trickier.   conditionValidator() takes a tbl_id that uses TblUtil.getTblById to resolve a tableModel.
+        *  This involves a fully functional redux store which is not available to our JS test environment at the moment.
+        *  So, we will 'fake' the return value of getTblById by 'mocking' that function
+        */
+        const aStringColumn = {
+            tableData: {
+                columns: [ {name: 'desc', type: 'char'}],
+            }
+        };
+
+        TblUtil.getTblById = jest.fn().mockReturnValue(aStringColumn);          // mock getTblById to return the aStringColumn table
+
+        let actual = FilterInfo.conditionValidator('=abc', 'a_fake_tbl_id', 'desc');
+        expect(actual.valid).toBe(true);
+        expect(actual.value).toBe("= 'abc'");      // the validator correctly insert space and quote around a value of a string column.
+
+        actual = FilterInfo.conditionValidator('abc', 'a_fake_tbl_id', 'desc');
+        expect(actual.valid).toBe(true);
+        expect(actual.value).toBe("like '%abc%'");      // the validator correctly convert it into a LIKE operator
+    });
+
+    test('autoCorrectConditions: numeric columns', () => {
+
+        const aNumericColumn = {
+            tableData: {
+                columns: [ {name: 'ra', type: 'double'}],
+            }
+        };
+
+        TblUtil.getTblById = jest.fn().mockReturnValue(aNumericColumn);          // once again mock getTblById to return the different (numeric) table
+
+        const {valid, value} = FilterInfo.conditionValidator('>1.23', 'a_fake_tbl_id', 'ra');
+        expect(valid).toBe(true);
+        expect(value).toBe('> 1.23');      // the validator correctly insert space and no quotes on numeric columns.
+    });
+
+});
+
diff --git a/src/firefly/js/tables/__tests__/TableUtil-test.js b/src/firefly/js/tables/__tests__/TableUtil-test.js
index 3e9a38ce71..1162332a1e 100644
--- a/src/firefly/js/tables/__tests__/TableUtil-test.js
+++ b/src/firefly/js/tables/__tests__/TableUtil-test.js
@@ -2,15 +2,14 @@ import {get} from 'lodash';
 
 import * as TblUtil from '../TableUtil.js';         // used for named import
 import TableUtil from '../TableUtil.js';            // using default import
-import {FilterInfo} from '../FilterInfo.js';
 import {SelectInfo} from '../SelectInfo';
 import {MetaConst} from '../../data/MetaConst';
-import {hasRowAccess} from '../TableUtil';
 import {dataReducer} from '../reducer/TableDataReducer.js';
 import {TABLE_LOADED} from '../TablesCntlr.js';
+import {NULL_TOKEN} from '../FilterInfo.js';
 
 
-describe('TableUtil:', () => {
+describe('TableUtil: ', () => {
 
     test('isTableLoaded', () => {
         // a simple test to ensure when a table is loaded.
@@ -96,10 +95,15 @@ describe('TableUtil:', () => {
             });
     });
 
+});
+
+
+describe('TableUtil: datarights', () => {
+
     test('DATARIGHTS_COL', () => {
         const table = {
             tableMeta: {[MetaConst.DATARIGHTS_COL]: 'a'},
-            totalRows: 6,
+            totalRows: 7,
             tableData: {
                 columns: [ {name: 'a'}, {name: 'b'}, {name: 'c'}],
                 data: [
@@ -114,13 +118,13 @@ describe('TableUtil:', () => {
             }
         };
 
-        expect(hasRowAccess(table, 0)).toBe(true);
-        expect(hasRowAccess(table, 1)).toBe(false);
-        expect(hasRowAccess(table, 2)).toBe(true);
-        expect(hasRowAccess(table, 3)).toBe(true);
-        expect(hasRowAccess(table, 4)).toBe(true);
-        expect(hasRowAccess(table, 5)).toBe(false);
-        expect(hasRowAccess(table, 6)).toBe(false);
+        expect(TblUtil.hasRowAccess(table, 0)).toBe(true);
+        expect(TblUtil.hasRowAccess(table, 1)).toBe(false);
+        expect(TblUtil.hasRowAccess(table, 2)).toBe(true);
+        expect(TblUtil.hasRowAccess(table, 3)).toBe(true);
+        expect(TblUtil.hasRowAccess(table, 4)).toBe(true);
+        expect(TblUtil.hasRowAccess(table, 5)).toBe(false);
+        expect(TblUtil.hasRowAccess(table, 6)).toBe(false);
     });
 
     test('RELEASE_DATE_COL', () => {
@@ -137,9 +141,9 @@ describe('TableUtil:', () => {
             }
         };
 
-        expect(hasRowAccess(table, 0)).toBe(true);
-        expect(hasRowAccess(table, 1)).toBe(false);
-        expect(hasRowAccess(table, 2)).toBe(false);
+        expect(TblUtil.hasRowAccess(table, 0)).toBe(true);
+        expect(TblUtil.hasRowAccess(table, 1)).toBe(false);
+        expect(TblUtil.hasRowAccess(table, 2)).toBe(false);
     });
 
     test('both RELEASE_DATE_COL and DATARIGHTS_COL', () => {
@@ -159,9 +163,9 @@ describe('TableUtil:', () => {
             }
         };
 
-        expect(hasRowAccess(table, 0)).toBe(true);
-        expect(hasRowAccess(table, 1)).toBe(true);
-        expect(hasRowAccess(table, 2)).toBe(false);
+        expect(TblUtil.hasRowAccess(table, 0)).toBe(true);
+        expect(TblUtil.hasRowAccess(table, 1)).toBe(true);
+        expect(TblUtil.hasRowAccess(table, 2)).toBe(false);
     });
 
     test('Proprietary data by ObsCore cnames', () => {
@@ -182,9 +186,9 @@ describe('TableUtil:', () => {
         const dataRoot = dataReducer({data:{id123: table}}, {type: TABLE_LOADED, payload: table});
         const otable = get(dataRoot, 'id123');
 
-        expect(hasRowAccess(otable, 0)).toBe(true);
-        expect(hasRowAccess(otable, 1)).toBe(true);
-        expect(hasRowAccess(otable, 2)).toBe(false);
+        expect(TblUtil.hasRowAccess(otable, 0)).toBe(true);
+        expect(TblUtil.hasRowAccess(otable, 1)).toBe(true);
+        expect(TblUtil.hasRowAccess(otable, 2)).toBe(false);
     });
 
     test('Proprietary data by utype', () => {
@@ -205,9 +209,9 @@ describe('TableUtil:', () => {
         const dataRoot = dataReducer({data:{id123: table}}, {type: TABLE_LOADED, payload: table});
         const otable = get(dataRoot, 'id123');
 
-        expect(hasRowAccess(otable, 0)).toBe(true);
-        expect(hasRowAccess(otable, 1)).toBe(true);
-        expect(hasRowAccess(otable, 2)).toBe(false);
+        expect(TblUtil.hasRowAccess(otable, 0)).toBe(true);
+        expect(TblUtil.hasRowAccess(otable, 1)).toBe(true);
+        expect(TblUtil.hasRowAccess(otable, 2)).toBe(false);
     });
 
     test('Proprietary data by UCD', () => {
@@ -229,55 +233,81 @@ describe('TableUtil:', () => {
         const otable = get(dataRoot, 'id123');
 
         // only release date matters
-        expect(hasRowAccess(otable, 0)).toBe(true);
-        expect(hasRowAccess(otable, 1)).toBe(false);
-        expect(hasRowAccess(otable, 2)).toBe(false);
+        expect(TblUtil.hasRowAccess(otable, 0)).toBe(true);
+        expect(TblUtil.hasRowAccess(otable, 1)).toBe(false);
+        expect(TblUtil.hasRowAccess(otable, 2)).toBe(false);
     });
 
 });
 
 
-describe('FilterInfo', () => {
+describe('TableUtil: client_table', () => {
+
+    const table = {
+        totalRows: 6,
+        tableData: {
+            columns: [  {name: 'c1', type: 'char', nullString: 'null'},
+                        {name: 'c2', type: 'double'},
+                        {name: 'c3', type: 'int'}
+            ],
+            data: [
+                ['abc'      , 0.123     ,  100      ],
+                [undefined  , -2.34     ,   -1      ],
+                ['123'      ,   0.0     , null      ],
+                [''         ,  null     ,   50      ],
+                [null       , 0.131     ,  -20      ],
+                ['ABC'      , undefined ,   undefined]
+            ],
+        }
+    };
+
+    test('Sort', () => {
+        // undefined is smallest, then null, then natural order
+        let res = TblUtil.processRequest(table, {sortInfo: 'ASC,c1'});
+        expect(TblUtil.getColumnValues(res, 'c1')).toEqual([undefined, null, '', '123', 'ABC', 'abc']);
+
+        res = TblUtil.processRequest(table, {sortInfo: 'DESC,c1'});
+        expect(TblUtil.getColumnValues(res, 'c1')).toEqual(['abc', 'ABC', '123', '', null, undefined]);
+
+        res = TblUtil.processRequest(table, {sortInfo: 'ASC,c2'});
+        expect(TblUtil.getColumnValues(res, 'c2')).toEqual([undefined, null, -2.34, 0.0, 0.123, 0.131]);
+
+        res = TblUtil.processRequest(table, {sortInfo: 'DESC,c2'});
+        expect(TblUtil.getColumnValues(res, 'c2')).toEqual([0.131, 0.123, 0.0, -2.34, null, undefined]);
+
+        res = TblUtil.processRequest(table, {sortInfo: 'ASC,c3'});
+        expect(TblUtil.getColumnValues(res, 'c3')).toEqual([undefined, null, -20, -1, 50, 100]);
+
+        res = TblUtil.processRequest(table, {sortInfo: 'DESC,c3'});
+        expect(TblUtil.getColumnValues(res, 'c3')).toEqual([100, 50, -1, -20, null, undefined]);
+    });
 
-    test('autoCorrectConditions: string columns', () => {
+    test('filter', () => {
 
-        /*
-        *  This test is a little trickier.   conditionValidator() takes a tbl_id that uses TblUtil.getTblById to resolve a tableModel.
-        *  This involves a fully functional redux store which is not available to our JS test environment at the moment.
-        *  So, we will 'fake' the return value of getTblById by 'mocking' that function
-        */
-        const aStringColumn = {
-            tableData: {
-                columns: [ {name: 'desc', type: 'char'}],
-            }
-        };
+        let res = TblUtil.processRequest(table, {filters: "c1 IN ('abc','')"});
+        expect(TblUtil.getColumnValues(res, 'c2')).toEqual([0.123, null, undefined]);       // filtering is not case sensitive. abc === ABC
 
-        TblUtil.getTblById = jest.fn().mockReturnValue(aStringColumn);          // mock getTblById to return the aStringColumn table
+        res = TblUtil.processRequest(table, {filters: `c1 IN ('abc', ${NULL_TOKEN})`});
+        expect(TblUtil.getColumnValues(res, 'c2')).toEqual([0.123, 0.131, undefined]);      // testing special NULL_TOKEN
 
-        let actual = FilterInfo.conditionValidator('=abc', 'a_fake_tbl_id', 'desc');
-        expect(actual.valid).toBe(true);
-        expect(actual.value).toBe("= 'abc'");      // the validator correctly insert space and quote around a value of a string column.
+        res = TblUtil.processRequest(table, {filters: 'c2 > 0'});
+        expect(TblUtil.getColumnValues(res, 'c2')).toEqual([0.123, 0.131]);                 // testing greater than (>)
 
-        actual = FilterInfo.conditionValidator('abc', 'a_fake_tbl_id', 'desc');
-        expect(actual.valid).toBe(true);
-        expect(actual.value).toBe("like '%abc%'");      // the validator correctly convert it into a LIKE operator
-    });
+        res = TblUtil.processRequest(table, {filters: 'c2 < 0'});
+        expect(TblUtil.getColumnValues(res, 'c2')).toEqual([-2.34]);                        // equality test, null and undefined are ignored
 
-    test('autoCorrectConditions: numeric columns', () => {
+        res = TblUtil.processRequest(table, {filters: 'c1 < a'});
+        expect(TblUtil.getColumnValues(res, 'c1')).toEqual(['123', '']);                    // testing less than (<) on string
 
-        const aNumericColumn = {
-            tableData: {
-                columns: [ {name: 'ra', type: 'double'}],
-            }
-        };
+        res = TblUtil.processRequest(table, {filters: 'c1 IS NULL'});
+        expect(TblUtil.getColumnValues(res, 'c2')).toEqual([-2.34, 0.131]);                 // testing IS NULL on a string column
 
-        TblUtil.getTblById = jest.fn().mockReturnValue(aNumericColumn);          // once again mock getTblById to return the different (numeric) table
+        res = TblUtil.processRequest(table, {filters: 'c2 IS NULL'});
+        expect(TblUtil.getColumnValues(res, 'c1')).toEqual(['', 'ABC']);                    // testing IS NULL on numeric column
 
-        const {valid, value} = FilterInfo.conditionValidator('>1.23', 'a_fake_tbl_id', 'ra');
-        expect(valid).toBe(true);
-        expect(value).toBe('> 1.23');      // the validator correctly insert space and no quotes on numeric columns.
+        res = TblUtil.processRequest(table, {filters: 'c2 IS NOT NULL'});
+        expect(TblUtil.getColumnValues(res, 'c1')).toEqual(['abc', undefined, '123', null]); // testing IS NOT NULL
     });
 
-
 });
 
diff --git a/src/firefly/js/tables/ui/BasicTableView.jsx b/src/firefly/js/tables/ui/BasicTableView.jsx
index ab4ea96c4d..e12c14f155 100644
--- a/src/firefly/js/tables/ui/BasicTableView.jsx
+++ b/src/firefly/js/tables/ui/BasicTableView.jsx
@@ -8,7 +8,7 @@ import FixedDataTable from 'fixed-data-table-2';
 import {wrapResizer} from '../../ui/SizeMeConfig.js';
 import {get, isEmpty} from 'lodash';
 
-import {tableTextView, getTableUiById, getProprietaryInfo, getTblById, hasRowAccess, uniqueTblUiId} from '../TableUtil.js';
+import {tableTextView, getTableUiById, getProprietaryInfo, getTblById, hasRowAccess, calcColumnWidths, uniqueTblUiId} from '../TableUtil.js';
 import {SelectInfo} from '../SelectInfo.js';
 import {FilterInfo} from '../FilterInfo.js';
 import {SortInfo} from '../SortInfo.js';
@@ -46,11 +46,6 @@ const BasicTableViewInternal = React.memo((props) => {
     const onFilter       = useCallback( doFilter.bind({callbacks, filterInfo}), [callbacks, filterInfo]);
     const onFilterSelected = useCallback( doFilterSelected.bind({callbacks, selectInfoCls}), [callbacks, selectInfoCls]);
 
-    useEffect( () => {
-        if (!columnWidths) {
-            dispatchTableUiUpdate({tbl_ui_id, columnWidths: makeColWidth(columns, data)});
-        }
-    });
     const headerHeight = 22 + (showUnits && 8) + (showTypes && 8) + (showFilters && 22);
     let totalColWidths = 0;
     if (!isEmpty(columns) && !isEmpty(columnWidths)) {
@@ -65,7 +60,7 @@ const BasicTableViewInternal = React.memo((props) => {
 
     useEffect( () => {
         const changes = {};
-        if (!columnWidths)                  changes.columnWidths = makeColWidth(columns, data);
+        if (!columnWidths)                  changes.columnWidths = columnWidthsInPixel(columns, data);
         if (adjScrollTop !== scrollTop)     changes.scrollTop = adjScrollTop;
         if (adjScrollLeft !== scrollLeft)   changes.scrollLeft = adjScrollLeft;
 
@@ -296,30 +291,9 @@ function correctScrollLeftIfNeeded(totalColWidths, scrollLeft, width, triggeredB
     return scrollLeft;
 }
 
-function calcMaxWidth(idx, col, data) {
-    let nchar = col.prefWidth || col.width;
-    if (!nchar) {
-        const label = col.label || col.name;
-        const hWidth = Math.max(
-            get(label, 'length', 0) + 2,
-            get(col, 'units.length', 0) + 2,
-            get(col, 'type.length', 0) + 2
-        );
-        nchar = hWidth;
-        for (const r in data) {
-            const w = get(data, [r, idx, 'length'], 0);
-            if (w > nchar) nchar = w;
-        }
-    }
-    return nchar * 7;
-}
-
-function makeColWidth(columns, data) {
-
-    return !columns ? {} : columns.reduce((widths, col, idx) => {
-        widths[idx] = calcMaxWidth(idx, col, data);
-        return widths;
-    }, {});
+function columnWidthsInPixel(columns, data) {
+    return calcColumnWidths(columns, data)
+            .map( (w) =>  (w + 2) * 7);
 }
 
 function rowClassNameGetter(tbl_id, hlRowIdx, startIdx) {
diff --git a/src/firefly/js/tables/ui/TablePanel.jsx b/src/firefly/js/tables/ui/TablePanel.jsx
index 63a1f4906f..bca9f43d5e 100644
--- a/src/firefly/js/tables/ui/TablePanel.jsx
+++ b/src/firefly/js/tables/ui/TablePanel.jsx
@@ -9,7 +9,7 @@ import shallowequal from 'shallowequal';
 
 import {flux} from '../../Firefly.js';
 import * as TblUtil from '../TableUtil.js';
-import {dispatchTableRemove, dispatchTblExpanded, dispatchTableSearch} from '../TablesCntlr.js';
+import {dispatchTableRemove, dispatchTblExpanded, dispatchTableFetch} from '../TablesCntlr.js';
 import {TablePanelOptions} from './TablePanelOptions.jsx';
 import {BasicTableView} from './BasicTableView.jsx';
 import {TableInfo} from './TableInfo.jsx';
@@ -22,7 +22,6 @@ import {HelpIcon} from '../../ui/HelpIcon.jsx';
 import {showTableDownloadDialog} from './TableSave.jsx';
 import {showOptionsPopup} from '../../ui/PopupUtil.jsx';
 import {BgMaskPanel} from '../../core/background/BgMaskPanel.jsx';
-import {getAppOptions} from '../../core/AppDataCntlr.js';
 
 //import INFO from 'html/images/icons-2014/24x24_Info.png';
 import FILTER from 'html/images/icons-2014/24x24_Filter.png';
@@ -346,7 +345,7 @@ function Loading({showTitle, tbl_id, title, removable, backgroundable}) {
 function TableError({tbl_id, message}) {
     const prevReq = TblUtil.getResultSetRequest(tbl_id);
     const reloadTable = () => {
-        dispatchTableSearch(JSON.parse(prevReq));
+        dispatchTableFetch(JSON.parse(prevReq));
     };
     return (
         <div className='TablePanel__error'>
diff --git a/src/firefly/js/tables/ui/TableRenderer.js b/src/firefly/js/tables/ui/TableRenderer.js
index 8938e4ba67..edacef226a 100644
--- a/src/firefly/js/tables/ui/TableRenderer.js
+++ b/src/firefly/js/tables/ui/TableRenderer.js
@@ -6,7 +6,7 @@ import React, {Component, PureComponent, useRef, useCallback} from 'react';
 import FixedDataTable from 'fixed-data-table-2';
 import {set, get, isEqual, pick} from 'lodash';
 
-import {FilterInfo, FILTER_CONDITION_TTIPS} from '../FilterInfo.js';
+import {FilterInfo, FILTER_CONDITION_TTIPS, NULL_TOKEN} from '../FilterInfo.js';
 import {isNumericType, tblDropDownId, getTblById, getColumn} from '../TableUtil.js';
 import {SortInfo} from '../SortInfo.js';
 import {InputField} from '../../ui/InputField.jsx';
@@ -20,6 +20,7 @@ import {CheckboxGroupInputField} from '../../ui/CheckboxGroupInputField';
 import {showDropDown, hideDropDown} from '../../ui/DialogRootContainer.jsx';
 import {FieldGroup} from '../../ui/FieldGroup';
 import {getFieldVal} from '../../fieldGroup/FieldGroupUtils.js';
+import {dispatchValueChange} from '../../fieldGroup/FieldGroupCntlr.js';
 import {useStoreConnector} from './../../ui/SimpleComponent.jsx';
 import {resolveHRefVal} from '../../util/VOAnalyzer.js';
 
@@ -117,26 +118,34 @@ function Filter({cname, onFilter, filterInfo, tbl_id}) {
     );
 }
 
-function EnumSelect({col, tbl_id, filterInfo, filterInfoCls, onFilter}) {
+function EnumSelect({col, tbl_id, filterInfoCls, onFilter}) {
     const {name, enumVals} = col || {};
     const groupKey = 'TableRenderer_enum';
     const fieldKey = tbl_id + '-' + name;
-    const options = col.enumVals.split(',')
-                        .map( (s) => s.trim())
-                        .map( (s) => ({label: s, value: s}) );
-    let value = '';
-    const filterBy = (filterInfoCls.getFilter(name) || '').match(/IN \((.+)\)/);
+    const options = enumVals.split(',')
+                        .map( (s) => {
+                            const value = s === '' ? '%EMPTY' : s;                  // because CheckboxGroupInputField does not support '' as an option, use '%EMPTY' as substitute
+                            const label = value === NULL_TOKEN ? '<NULL>' : value === '%EMPTY' ? '<EMPTY_STR>' : value;
+                            return {label, value};
+                        } );
+    let value;
+    const filterBy = (filterInfoCls.getFilter(name) || '').match(/IN \((.+)\)/i);
     if (filterBy) {
         // IN condition is used, set value accordingly.  remove enclosed quote if exists
         value = filterBy[1].split(',')
-                           .map( (s) => s.trim().replace(/^'(.+)'$/, '$1'))
+                           .map( (s) => s.trim().replace(/^'(.*)'$/, '$1'))
+                           .map((s) => s === '' ? '%EMPTY' : s)                 // convert '' to %EMPTY
                            .join(',');
     }
 
     const hideEnumSelect = () => hideDropDown(tblDropDownId(tbl_id));
+    const onClear = () => {
+        dispatchValueChange({fieldKey, groupKey, value: '', valid: true});
+    };
     const onApply = () => {
-        let value = getFieldVal(groupKey, fieldKey, '');
+        let value = getFieldVal(groupKey, fieldKey);
         if (value) {
+            value = value.split(',').map((s) => s === '%EMPTY' ? '' : s).join();           // convert %EMPTY back into ''
             value = isNumericType(col) ? value :
                     value.split(',')
                          .map((s) => `'${s.trim()}'`).join(',');
@@ -149,7 +158,8 @@ function EnumSelect({col, tbl_id, filterInfo, filterInfoCls, onFilter}) {
     return (
         <FieldGroup groupKey='TableRenderer_enum' style={{minWidth: 100}}>
             <div style={{display: 'inline-flex', marginBottom: 5, width: '100%', justifyContent: 'space-between'}}>
-                <div className='ff-href' style={{marginLeft: 3, fontSize: 13}} onClick={onApply}>filter</div>
+                <div className='ff-href' style={{marginLeft: 3, fontSize: 13}} onClick={onApply} title='Apply selected filter'>filter</div>
+                <div className='ff-href' style={{marginLeft: 3, fontSize: 13}} onClick={onClear} title='Clear selection'>clear</div>
                 <div className='btn-close' onClick={hideEnumSelect} style={{margin: -2, fontSize: 12}}/>
             </div>
             <CheckboxGroupInputField {...{fieldKey, alignment: 'vertical', options, initialState:{value}}}/>
diff --git a/src/firefly/test/edu/caltech/ipac/astro/IpacTableReaderTest.java b/src/firefly/test/edu/caltech/ipac/astro/IpacTableReaderTest.java
index 7fb49575ab..75f2cd1622 100644
--- a/src/firefly/test/edu/caltech/ipac/astro/IpacTableReaderTest.java
+++ b/src/firefly/test/edu/caltech/ipac/astro/IpacTableReaderTest.java
@@ -406,6 +406,35 @@ public void testNoData() {
 
     }
 
+    /**
+     * This test IpacTableReader handling of NULL related values
+     */
+    @Test
+    public void testNullValues() {
+        String input =  "|ra      |dec    |spec   |SpType   |\n" +
+                        "|double  |double |char   |char     |\n" +
+                        "|        |       |       |         |\n" +
+                        "|null    |       |       |null     |\n" +
+                        " 123.4    5.67    null    K6Ve-1    \n" +
+                        " null                               \n" +
+                        " 123.4    5.67    abc     null      \n";
+        try{
+            DataGroup dg = IpacTableReader.read(asInputStream(input));
+
+            Assert.assertNull(dg.getData("ra", 1));                         // value is same as NULL_STR, so value should be read in as null
+            Assert.assertNull(dg.getData("dec", 1));                        // value is same as NULL_STR, so value should be read in as null
+
+            Assert.assertEquals("null", dg.getData("spec", 0));    // NULL_STR is empty_str, so null should be interpreted as a string
+            Assert.assertNull(dg.getData("spec", 1));                       // value is same as NULL_STR, so value should be read in as null
+
+            Assert.assertEquals("", dg.getData("SpType", 1));      // NULL_STR is 'null', so blank should be interpreted as an empty string
+            Assert.assertNull(dg.getData("SpType", 2));                     // value is same as NULL_STR, so value should be read in as null
+        } catch (IOException e) {
+            Assert.fail("Unexpected read error:" + e.getMessage());
+        }
+
+    }
+
     @Test
     /**
      * This test calls the method IpacTableReader.readIpacTable to read a table which has one datum under "|".