[Tarantool-patches] [PATCH v1 02/21] sql: refactor GREATEST() and LEAST() functions
imeevma at tarantool.org
imeevma at tarantool.org
Thu Nov 11 13:48:52 MSK 2021
Part of #4145
---
src/box/sql/func.c | 113 +++++++++++++++++++++++----------------------
1 file changed, 57 insertions(+), 56 deletions(-)
diff --git a/src/box/sql/func.c b/src/box/sql/func.c
index 0cd8f8f69..40bdbf739 100644
--- a/src/box/sql/func.c
+++ b/src/box/sql/func.c
@@ -782,6 +782,34 @@ func_char(struct sql_context *ctx, int argc, struct Mem *argv)
mem_set_str_allocated(ctx->pOut, str, len);
}
+/**
+ * Implementation of the GREATEST() and LEAST() functions.
+ *
+ * The GREATEST() function returns the largest of the given arguments.
+ * The LEAST() function returns the smallest of the given arguments.
+ */
+static void
+func_greatest_least(struct sql_context *ctx, int argc, struct Mem *argv)
+{
+ assert(argc > 1);
+ int mask = ctx->func->def->name[0] == 'G' ? -1 : 0;
+ assert(ctx->func->def->name[0] == 'G' ||
+ ctx->func->def->name[0] == 'L');
+
+ if (mem_is_null(&argv[0]))
+ return;
+ int best = 0;
+ for (int i = 1; i < argc; ++i) {
+ if (mem_is_null(&argv[i]))
+ return;
+ int cmp = mem_cmp_scalar(&argv[best], &argv[i], ctx->coll);
+ if ((cmp ^ mask) >= 0)
+ best = i;
+ }
+ if (mem_copy(ctx->pOut, &argv[best]) != 0)
+ ctx->is_aborted = true;
+}
+
static const unsigned char *
mem_as_ustr(struct Mem *mem)
{
@@ -829,37 +857,6 @@ sql_func_uuid(struct sql_context *ctx, int argc, struct Mem *argv)
mem_set_uuid(ctx->pOut, &uuid);
}
-/*
- * Implementation of the non-aggregate min() and max() functions
- */
-static void
-minmaxFunc(struct sql_context *context, int argc, struct Mem *argv)
-{
- int i;
- int iBest;
- struct coll *pColl;
- struct func *func = context->func;
- int mask = sql_func_flag_is_set(func, SQL_FUNC_MAX) ? -1 : 0;
- if (argc < 2) {
- diag_set(ClientError, ER_FUNC_WRONG_ARG_COUNT,
- mask ? "GREATEST" : "LEAST", "at least two", argc);
- context->is_aborted = true;
- return;
- }
- pColl = context->coll;
- assert(mask == -1 || mask == 0);
- iBest = 0;
- if (mem_is_null(&argv[0]))
- return;
- for (i = 1; i < argc; i++) {
- if (mem_is_null(&argv[i]))
- return;
- if ((mem_cmp_scalar(&argv[iBest], &argv[i], pColl) ^ mask) >= 0)
- iBest = i;
- }
- sql_result_value(context, &argv[iBest]);
-}
-
/*
* Return the type of the argument.
*/
@@ -1788,13 +1785,11 @@ static struct sql_func_dictionary dictionaries[] = {
{"CHAR_LENGTH", 1, 1, 0, true, 0, NULL},
{"COALESCE", 2, SQL_MAX_FUNCTION_ARG, SQL_FUNC_COALESCE, true, 0, NULL},
{"COUNT", 0, 1, SQL_FUNC_AGG, false, 0, NULL},
- {"GREATEST", 2, SQL_MAX_FUNCTION_ARG, SQL_FUNC_MAX | SQL_FUNC_NEEDCOLL,
- true, 0, NULL},
+ {"GREATEST", 2, SQL_MAX_FUNCTION_ARG, SQL_FUNC_NEEDCOLL, true, 0, NULL},
{"GROUP_CONCAT", 1, 2, SQL_FUNC_AGG, false, 0, NULL},
{"HEX", 1, 1, 0, true, 0, NULL},
{"IFNULL", 2, 2, SQL_FUNC_COALESCE, true, 0, NULL},
- {"LEAST", 2, SQL_MAX_FUNCTION_ARG, SQL_FUNC_MIN | SQL_FUNC_NEEDCOLL,
- true, 0, NULL},
+ {"LEAST", 2, SQL_MAX_FUNCTION_ARG, SQL_FUNC_NEEDCOLL, true, 0, NULL},
{"LENGTH", 1, 1, SQL_FUNC_LENGTH, true, 0, NULL},
{"LIKE", 2, 3, SQL_FUNC_LIKE | SQL_FUNC_NEEDCOLL, true, 0, NULL},
{"LIKELIHOOD", 2, 2, SQL_FUNC_UNLIKELY, true, 0, NULL},
@@ -1876,19 +1871,20 @@ static struct sql_func_definition definitions[] = {
{"COUNT", 1, {FIELD_TYPE_ANY}, FIELD_TYPE_INTEGER, step_count,
fin_count},
- {"GREATEST", -1, {FIELD_TYPE_INTEGER}, FIELD_TYPE_INTEGER, minmaxFunc,
- NULL},
- {"GREATEST", -1, {FIELD_TYPE_DOUBLE}, FIELD_TYPE_DOUBLE, minmaxFunc,
- NULL},
- {"GREATEST", -1, {FIELD_TYPE_NUMBER}, FIELD_TYPE_NUMBER, minmaxFunc,
- NULL},
+ {"GREATEST", -1, {FIELD_TYPE_INTEGER}, FIELD_TYPE_INTEGER,
+ func_greatest_least, NULL},
+ {"GREATEST", -1, {FIELD_TYPE_DOUBLE}, FIELD_TYPE_DOUBLE,
+ func_greatest_least, NULL},
+ {"GREATEST", -1, {FIELD_TYPE_NUMBER}, FIELD_TYPE_NUMBER,
+ func_greatest_least, NULL},
{"GREATEST", -1, {FIELD_TYPE_VARBINARY}, FIELD_TYPE_VARBINARY,
- minmaxFunc, NULL},
- {"GREATEST", -1, {FIELD_TYPE_UUID}, FIELD_TYPE_UUID, minmaxFunc, NULL},
- {"GREATEST", -1, {FIELD_TYPE_STRING}, FIELD_TYPE_STRING, minmaxFunc,
- NULL},
- {"GREATEST", -1, {FIELD_TYPE_SCALAR}, FIELD_TYPE_SCALAR, minmaxFunc,
- NULL},
+ func_greatest_least, NULL},
+ {"GREATEST", -1, {FIELD_TYPE_UUID}, FIELD_TYPE_UUID,
+ func_greatest_least, NULL},
+ {"GREATEST", -1, {FIELD_TYPE_STRING}, FIELD_TYPE_STRING,
+ func_greatest_least, NULL},
+ {"GREATEST", -1, {FIELD_TYPE_SCALAR}, FIELD_TYPE_SCALAR,
+ func_greatest_least, NULL},
{"GROUP_CONCAT", 1, {FIELD_TYPE_STRING}, FIELD_TYPE_STRING,
step_group_concat, NULL},
@@ -1903,15 +1899,20 @@ static struct sql_func_definition definitions[] = {
{"IFNULL", 2, {FIELD_TYPE_ANY, FIELD_TYPE_ANY}, FIELD_TYPE_SCALAR,
sql_builtin_stub, NULL},
- {"LEAST", -1, {FIELD_TYPE_INTEGER}, FIELD_TYPE_INTEGER, minmaxFunc,
- NULL},
- {"LEAST", -1, {FIELD_TYPE_DOUBLE}, FIELD_TYPE_DOUBLE, minmaxFunc, NULL},
- {"LEAST", -1, {FIELD_TYPE_NUMBER}, FIELD_TYPE_NUMBER, minmaxFunc, NULL},
- {"LEAST", -1, {FIELD_TYPE_VARBINARY}, FIELD_TYPE_VARBINARY, minmaxFunc,
- NULL},
- {"LEAST", -1, {FIELD_TYPE_UUID}, FIELD_TYPE_UUID, minmaxFunc, NULL},
- {"LEAST", -1, {FIELD_TYPE_STRING}, FIELD_TYPE_STRING, minmaxFunc, NULL},
- {"LEAST", -1, {FIELD_TYPE_SCALAR}, FIELD_TYPE_SCALAR, minmaxFunc, NULL},
+ {"LEAST", -1, {FIELD_TYPE_INTEGER}, FIELD_TYPE_INTEGER,
+ func_greatest_least, NULL},
+ {"LEAST", -1, {FIELD_TYPE_DOUBLE}, FIELD_TYPE_DOUBLE,
+ func_greatest_least, NULL},
+ {"LEAST", -1, {FIELD_TYPE_NUMBER}, FIELD_TYPE_NUMBER,
+ func_greatest_least, NULL},
+ {"LEAST", -1, {FIELD_TYPE_VARBINARY}, FIELD_TYPE_VARBINARY,
+ func_greatest_least, NULL},
+ {"LEAST", -1, {FIELD_TYPE_UUID}, FIELD_TYPE_UUID,
+ func_greatest_least, NULL},
+ {"LEAST", -1, {FIELD_TYPE_STRING}, FIELD_TYPE_STRING,
+ func_greatest_least, NULL},
+ {"LEAST", -1, {FIELD_TYPE_SCALAR}, FIELD_TYPE_SCALAR,
+ func_greatest_least, NULL},
{"LENGTH", 1, {FIELD_TYPE_STRING}, FIELD_TYPE_INTEGER, func_char_length,
NULL},
--
2.25.1
More information about the Tarantool-patches
mailing list