Merge pull request #138 from Mytherin/issue136

Fix #136 - correctly deal with decimals that have many leading zeros
duckdb · Nov 28, 2023 · cd6d147 · cd6d147
2 parents 0834101 + d34ecbc
commit cd6d147
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Showing 3 changed files with 65 additions and 1 deletion.
diff --git a/src/include/postgres_binary_reader.hpp b/src/include/postgres_binary_reader.hpp
@@ -231,7 +231,7 @@ struct PostgresBinaryReader {
 			auto fractional_power_correction = fractional_power - config.scale;
 			D_ASSERT(fractional_power_correction < 20);
 			fractional_part = 0;
-			for (auto i = config.weight + 1; i < config.ndigits; i++) {
+			for (int32_t i = MaxValue<int32_t>(0, config.weight + 1); i < config.ndigits; i++) {
 				if (i + 1 < config.ndigits) {
 					// more digits remain - no need to compensate yet
 					fractional_part *= NBASE;

diff --git a/test/all_pg_types.sql b/test/all_pg_types.sql
@@ -185,3 +185,30 @@ INSERT INTO mixed_arrays VALUES (
 INSERT INTO mixed_arrays VALUES (
 	ARRAY[1, 2, 3]
 );
+
+-- Issue #136 - Inconsistent results from querying postgres numeric columns
+create TABLE public_amounts (
+    id bigint NOT NULL,
+    rate numeric NOT NULL
+);
+insert into public_amounts values
+   (1, 0.67),
+   (2, 0.067),
+   (3, 0.0067),
+   (4, 0.00067),
+   (5, 0.000067),
+   (6, 0.0000067),
+   (7, 0.00000067),
+   (8, 0.000000067),
+   (9, 0.0000000067),
+   (10, 0.00000000067),
+   (11, 0.000000000067),
+   (12, 0.0000000000067),
+   (13, 0.00000000000067),
+   (14, 0.000000000000067),
+   (15, 0.0000000000000067),
+   (16, 0.00000000000000067),
+   (17, 0.000000000000000067),
+   (18, 0.0000000000000000067),
+   (19, 0.00000000000000000067),
+   (20, 0.000000000000000000067);
diff --git a/test/sql/storage/bug136.test b/test/sql/storage/bug136.test
@@ -0,0 +1,37 @@
+# name: test/sql/storage/bug136.test
+# description: Issue #136 - Inconsistent results from querying postgres numeric columns
+# group: [storage]
+
+require postgres_scanner
+
+require-env POSTGRES_TEST_DATABASE_AVAILABLE
+
+statement ok
+ATTACH 'dbname=postgresscanner' AS s (TYPE POSTGRES)
+
+statement ok
+USE s;
+
+query II
+SELECT * FROM public_amounts ORDER BY id
+----
+1	0.67
+2	0.067
+3	0.0067
+4	0.00067
+5	0.000067
+6	0.0000067
+7	0.00000067
+8	0.000000067
+9	0.0000000067
+10	0.00000000067
+11	0.000000000067
+12	0.0000000000067
+13	0.00000000000067
+14	0.000000000000067
+15	0.0000000000000067
+16	0.00000000000000067
+17	0.000000000000000067
+18	0.0000000000000000067
+19	0.00000000000000000067
+20	0.000000000000000000067