Merge: Fix >= and <= operators for date queries

This adds two missing branches in the `getDateWhereClause` function and fixes an consistency in the `constructDateTimeWhereClauseForColumn` function.

# Focus

1. Don't let the whitespace changes confuse you.
2. The changes in `constructDateTimeWhereClauseForColumn` merely add an "OR value_ns IS NULL".
3. The changes in `getDataWhereClause` add an ELSEIF branch for each operator.

CHANGELOG.md

@@ -47,6 +47,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed ###
 
+* Fixed the `>=` and `<=` operators for comparisons in POV query filters with
+  stored DATE values. The fix makes the implementation consistent
+  However, the current definition and implementation of the
+  `>=` and `<=` operators for date and datetime is unintuitive and the operators
+  should have another name. Something like "overlap with or smaller/greater
+  than".
 * Semi-fix in `retrieveEntityParents`. The old implementation was buggy and
   would return no parent name or even a wrong one for old entity versions in
   some cases. The semi-fix will allways return the current name of the parent

procedures/query/getDateTimeWhereClause.sql

@@ -85,7 +85,14 @@ BEGIN
             RETURN CONCAT(" ",
                 seconds_col, operator, vDateTimeSecLow, IF(vDateTimeNSLow IS NULL, '', CONCAT(' OR (',seconds_col,'=', vDateTimeSecLow, ' AND ',nanos_col, operator, vDateTimeNSLow, ')')));
         ELSEIF operator = '>=' or operator = '<=' THEN
-            RETURN CONCAT(" ",seconds_col, operator, vDateTimeSecLow, IF(vDateTimeNSLow IS NULL, '', CONCAT(' AND (',seconds_col, operator_prefix, vDateTimeSecLow, ' OR ',nanos_col, operator, vDateTimeNSLow, ')')));
+            RETURN CONCAT(
+                " ", seconds_col, operator, vDateTimeSecLow,
+                IF(vDateTimeNSLow IS NULL,
+                    '',
+                    CONCAT(
+                        ' AND (', seconds_col, operator_prefix, vDateTimeSecLow,
+                        ' OR ', nanos_col, operator, vDateTimeNSLow,
+                        ' OR ', nanos_col, ' IS NULL)')));
         ELSEIF operator = "(" THEN
             RETURN IF(vDateTimeNSLow IS NULL,CONCAT(" ",seconds_col,"=", vDateTimeSecLow),CONCAT(" ",seconds_col,"=",vDateTimeSecLow," AND ",nanos_col,"=",vDateTimeNSLow));
         ELSEIF operator = "!(" THEN
@@ -106,15 +113,20 @@ DELIMITER //
 CREATE FUNCTION db_2_0.getDateWhereClause(vDateTimeDotNotation VARCHAR(255), operator CHAR(4)) RETURNS VARCHAR(20000) DETERMINISTIC
 BEGIN
     DECLARE isInterval INTEGER DEFAULT LOCATE('--',vDateTimeDotNotation);
+    -- ILB is short for Inclusive Lower Boundary
     DECLARE vILB VARCHAR(255) DEFAULT IF(isInterval != 0, SUBSTRING_INDEX(vDateTimeDotNotation, '--', 1), vDateTimeDotNotation);
+    -- EUB is short for Exclusive Upper Boundary
     DECLARE vEUB VARCHAR(255) DEFAULT IF(isInterval != 0, SUBSTRING_INDEX(vDateTimeDotNotation, '--', -1), NULL);
     DECLARE vILB_Date INTEGER DEFAULT SUBSTRING_INDEX(vILB, '.', 1);
     DECLARE vEUB_Date INTEGER DEFAULT SUBSTRING_INDEX(vEUB, '.', 1);
+    -- hasTime is actually hasNotTime
     DECLARE hasTime INTEGER DEFAULT LOCATE('.NULL.NULL',vILB);
+    -- Day of Month (0-31, 0 means any)
     DECLARE dom INTEGER DEFAULT vILB_Date % 100;
+    -- Month (0-12, 0 means any)
     DECLARE mon INTEGER DEFAULT ((vILB_Date % 10000) - dom) / 100;
+    -- Year
     DECLARE yea INTEGER DEFAULT (vILB_Date - (vILB_Date % 10000)) / 10000;
-    SELECT vILB_Date != vEUB_Date INTO isInterval;
 
     IF operator = '=' and hasTime != 0 THEN
         RETURN CONCAT(" subdata.value=", vILB_Date);
@@ -161,6 +173,32 @@ BEGIN
         ELSE
             RETURN CONCAT(" subdata.value>=",vEUB_Date);
         END IF;
+    ELSEIF operator = "<=" THEN
+        IF mon != 0 and dom != 0 THEN
+            -- Full date YYYY-MM-DD
+            RETURN CONCAT(" subdata.value<=", vILB_Date,
+                          " or (subdata.value<=", yea*10000 + mon*100, " and subdata.value%100=0)");
+        ELSEIF mon != 0 THEN
+            -- Date is fragment YYYY-MM
+            RETURN CONCAT(" subdata.value<", vEUB_Date);
+        ELSE
+            -- Date is fragment YYYY
+            RETURN CONCAT(" subdata.value<", vEUB_Date);
+        END IF;
+    ELSEIF operator = ">=" THEN
+        IF mon != 0 and dom != 0 THEN
+            -- Full date YYYY-MM-DD
+            RETURN CONCAT(" subdata.value>=", vILB_Date,
+                          " or (subdata.value>=", yea*10000 + mon*100, " and subdata.value%100=0)" +
+                          " or (subdata.value>=", yea*10000, " and subdata.value%10000=0)");
+        ELSEIF mon != 0 THEN
+            -- Date is fragment YYYY-MM
+            RETURN CONCAT(" subdata.value>=", yea*10000 + mon*100,
+                          " or (subdata.value>=", yea*10000, " and subdata.value%10000=0)");
+        ELSE
+            -- Date is fragment YYYY
+            RETURN CONCAT(" subdata.value>=", yea*10000);
+        END IF;
     END IF;
 
     return ' 0=1';