[
https://issues.apache.org/jira/browse/CALCITE-6740?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
hongyu guo updated CALCITE-6740:
--------------------------------
Summary: Case statements may generate too many same code (was: Case
statements may generate too may same code)
> Case statements may generate too many same code
> -----------------------------------------------
>
> Key: CALCITE-6740
> URL: https://issues.apache.org/jira/browse/CALCITE-6740
> Project: Calcite
> Issue Type: Bug
> Components: core
> Affects Versions: 1.38.0
> Reporter: hongyu guo
> Priority: Major
> Fix For: 1.39.0
>
>
> reproduce
> {code:java}
> String sql = "with \"t\" as (select case "
> + "when \"store_id\" = 1 then '1' "
> + "when \"store_id\" = 2 then '2' "
> + "when \"store_id\" = 3 then '3' "
> + "when \"store_id\" = 4 then '4' "
> + "else '0' end as \"myid\" from (values (1),(2),(3),(6)) as
> \"tt\"(\"store_id\"))\n"
> + "select case "
> + "when \"myid\" = '1' then '11' "
> + "when \"myid\" = '2' then '22' "
> + "when \"myid\" = '3' then '33' "
> + "when \"myid\" = '4' then '44' "
> + "else '0' end as \"res\" from \"t\"";
> CalciteAssert.that()
> .query(sql)
> .returns("res=11\\nres=22\\nres=33\\nres=0 \\n");
> {code}
> generated code:
> {code:java}
> /* 1 */ public org.apache.calcite.linq4j.Enumerable bind(final
> org.apache.calcite.DataContext root) {
> /* 2 */ final org.apache.calcite.linq4j.Enumerable _inputEnumerable =
> org.apache.calcite.linq4j.Linq4j.asEnumerable(new Integer[] {
> /* 3 */ 1,
> /* 4 */ 2,
> /* 5 */ 3,
> /* 6 */ 6});
> /* 7 */ return new org.apache.calcite.linq4j.AbstractEnumerable(){
> /* 8 */ public org.apache.calcite.linq4j.Enumerator enumerator() {
> /* 9 */ return new org.apache.calcite.linq4j.Enumerator(){
> /* 10 */ public final org.apache.calcite.linq4j.Enumerator
> inputEnumerator = _inputEnumerable.enumerator();
> /* 11 */ public void reset() {
> /* 12 */ inputEnumerator.reset();
> /* 13 */ }
> /* 14 */
> /* 15 */ public boolean moveNext() {
> /* 16 */ return inputEnumerator.moveNext();
> /* 17 */ }
> /* 18 */
> /* 19 */ public void close() {
> /* 20 */ inputEnumerator.close();
> /* 21 */ }
> /* 22 */
> /* 23 */ public Object current() {
> /* 24 */ String case_when_value;
> /* 25 */ String case_when_value0;
> /* 26 */ final int current =
> org.apache.calcite.runtime.SqlFunctions.toInt(inputEnumerator.current());
> /* 27 */ if (current == 1) {
> /* 28 */ case_when_value0 = "1";
> /* 29 */ } else {
> /* 30 */ if (current == 2) {
> /* 31 */ case_when_value0 = "2";
> /* 32 */ } else {
> /* 33 */ if (current == 3) {
> /* 34 */ case_when_value0 = "3";
> /* 35 */ } else {
> /* 36 */ if (current == 4) {
> /* 37 */ case_when_value0 = "4";
> /* 38 */ } else {
> /* 39 */ case_when_value0 = "0";
> /* 40 */ }
> /* 41 */ }
> /* 42 */ }
> /* 43 */ }
> /* 44 */ if (case_when_value0 != null &&
> org.apache.calcite.runtime.SqlFunctions.eq(case_when_value0, "1")) {
> /* 45 */ case_when_value = "11";
> /* 46 */ } else {
> /* 47 */ String case_when_value1;
> /* 48 */ if (current == 1) {
> /* 49 */ case_when_value1 = "1";
> /* 50 */ } else {
> /* 51 */ if (current == 2) {
> /* 52 */ case_when_value1 = "2";
> /* 53 */ } else {
> /* 54 */ if (current == 3) {
> /* 55 */ case_when_value1 = "3";
> /* 56 */ } else {
> /* 57 */ if (current == 4) {
> /* 58 */ case_when_value1 = "4";
> /* 59 */ } else {
> /* 60 */ case_when_value1 = "0";
> /* 61 */ }
> /* 62 */ }
> /* 63 */ }
> /* 64 */ }
> /* 65 */ if (case_when_value1 != null &&
> org.apache.calcite.runtime.SqlFunctions.eq(case_when_value1, "2")) {
> /* 66 */ case_when_value = "22";
> /* 67 */ } else {
> /* 68 */ String case_when_value2;
> /* 69 */ if (current == 1) {
> /* 70 */ case_when_value2 = "1";
> /* 71 */ } else {
> /* 72 */ if (current == 2) {
> /* 73 */ case_when_value2 = "2";
> /* 74 */ } else {
> /* 75 */ if (current == 3) {
> /* 76 */ case_when_value2 = "3";
> /* 77 */ } else {
> /* 78 */ if (current == 4) {
> /* 79 */ case_when_value2 = "4";
> /* 80 */ } else {
> /* 81 */ case_when_value2 = "0";
> /* 82 */ }
> /* 83 */ }
> /* 84 */ }
> /* 85 */ }
> /* 86 */ if (case_when_value2 != null &&
> org.apache.calcite.runtime.SqlFunctions.eq(case_when_value2, "3")) {
> /* 87 */ case_when_value = "33";
> /* 88 */ } else {
> /* 89 */ String case_when_value3;
> /* 90 */ if (current == 1) {
> /* 91 */ case_when_value3 = "1";
> /* 92 */ } else {
> /* 93 */ if (current == 2) {
> /* 94 */ case_when_value3 = "2";
> /* 95 */ } else {
> /* 96 */ if (current == 3) {
> /* 97 */ case_when_value3 = "3";
> /* 98 */ } else {
> /* 99 */ if (current == 4) {
> /* 100 */ case_when_value3 = "4";
> /* 101 */ } else {
> /* 102 */ case_when_value3 = "0";
> /* 103 */ }
> /* 104 */ }
> /* 105 */ }
> /* 106 */ }
> /* 107 */ if (case_when_value3 != null &&
> org.apache.calcite.runtime.SqlFunctions.eq(case_when_value3, "4")) {
> /* 108 */ case_when_value = "44";
> /* 109 */ } else {
> /* 110 */ case_when_value = "0 ";
> /* 111 */ }
> /* 112 */ }
> /* 113 */ }
> /* 114 */ }
> /* 115 */ return case_when_value;
> /* 116 */ }
> /* 117 */
> /* 118 */ };
> /* 119 */ }
> /* 120 */
> /* 121 */ };
> /* 122 */ }
> /* 123 */
> /* 124 */
> /* 125 */ public Class getElementType() {
> /* 126 */ return java.lang.String.class;
> /* 127 */ }
> /* 128 */
> /* 129 */
> {code}
> The code used to calculate the `t.myid` field has been repeated multiple
> times.
> After my debugging, I found that in the
> [RexToLixTranslator#implementRecursively|https://github.com/apache/calcite/blob/648a832e0b3abc0f1cd4887847bdef7c133cb383/core/src/main/java/org/apache/calcite/adapter/enumerable/RexToLixTranslator.java#L1464]
> method, the
> [RexToLixTranslator#setBlock|https://github.com/apache/calcite/blob/648a832e0b3abc0f1cd4887847bdef7c133cb383/core/src/main/java/org/apache/calcite/adapter/enumerable/RexToLixTranslator.java#L1129]
> method was called to create a new translator, but the new translator did not
> copy the result cache *rexResultMap* in the original translator.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
