Add support for the CONCAT() and CONCAT_WS() SQL functions, modeled after

the PostgreSQL behavior.

FossilOrigin-Name: 0b434ca7aa19eff4ad134a8c6f88f6a7ccab88864faa55e93579a2462d8ac3bc

manifest

@@ -1,5 +1,5 @@
-C Change\sa\svariable\sfrom\s"int"\sto\s"i64"\sto\smake\sit\seasier\sto\sprove\sthat\sit\scannot\soverflow.
+C Add\ssupport\sfor\sthe\sCONCAT()\sand\sCONCAT_WS()\sSQL\sfunctions,\smodeled\safter\nthe\sPostgreSQL\sbehavior.
-D 2023-08-29T10:50:11.066
+D 2023-08-29T15:24:41.645
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -653,7 +653,7 @@ F src/delete.c cb766727c78e715f9fb7ec8a7d03658ed2a3016343ca687acfcec9083cdca500
 F src/expr.c 1affe0cc049683ef0ef3545d9b6901508556b0ef7e2892a344c3df6d7288d79d
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c a7fcbf7e66d14dbb73cf49f31489ebf66d0e6006c62b95246924a3bae9f37b36
-F src/func.c f480d46974ecc84fefdd429377158981b974e0e33d656f1b0e919ba7c4bdd390
+F src/func.c c96c7f55b97493ce278937e6ab6578a866b7e5d6dd486d58b220e9d17e88a750
 F src/global.c 29f56a330ed9d1b5cd9b79ac0ca36f97ac3afc730ff8bfa987b0db9e559d684d
 F src/hash.c 9ee4269fb1d6632a6fecfb9479c93a1f29271bddbbaf215dd60420bcb80c7220
 F src/hash.h 3340ab6e1d13e725571d7cee6d3e3135f0779a7d8e76a9ce0a85971fa3953c51
@@ -1180,6 +1180,7 @@ F test/func5.test 863e6d1bd0013d09c17236f8a13ea34008dd857d87d85a13a673960e4c25d8
 F test/func6.test 9cc9b1f43b435af34fe1416eb1e318c8920448ea7a6962f2121972f5215cb9b0
 F test/func7.test adbfc910385a6ffd15dc47be3c619ef070c542fcb7488964badb17b2d9a4d080
 F test/func8.test c4e2ecacf9f16e47a245e7a25fbabcc7e78f9c7c41a80f158527cdfdc6dd299d
+F test/func9.test b32d313f679aa9698d52f39519d301c3941823cb72b4e23406c210eadd82c824
 F test/fuzz-oss1.test 514dcabb24687818ea949fa6760229eaacad74ca70157743ef36d35bbe01ffb0
 F test/fuzz.test 4608c1310cff4c3014a84bcced6278139743e080046e5f6784b0de7b069371d8
 F test/fuzz2.test 76dc35b32b6d6f965259508508abce75a6c4d7e1
@@ -2108,8 +2109,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 6c83e31fa96f65b61377c0c801cc32b3c8ca27a0c8442f860364bec258c003cb
+P 00a8b3a263f3537588063ce42fad6e21fa343dad850b086d0929ed1617eb44fc
-R 703966de64a45733a2ec15e9ba123f27
+R 73410e2beee6b3d9558e014cdb959353
-U dan
+U drh
-Z cdc3674e70b09e1a4bfbc46bbf505365
+Z 75edcaca9693bb69bba026024423283c
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-00a8b3a263f3537588063ce42fad6e21fa343dad850b086d0929ed1617eb44fc
+0b434ca7aa19eff4ad134a8c6f88f6a7ccab88864faa55e93579a2462d8ac3bc

src/func.c

@@ -1550,6 +1550,81 @@ static void trimFunc(
   sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT);
 }
 
+/* The core implementation of the CONCAT(...) and CONCAT_WS(SEP,...)
+** functions.
+**
+** Return a string value that is the concatenation of all non-null
+** entries in argv[].  Use zSep as the separator.
+*/
+static void concatFuncCore(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv,
+  int nSep,
+  const char *zSep
+){
+  i64 j, k, n = 0;
+  int i;
+  char *z;
+  for(i=0; i<argc; i++){
+    n += sqlite3_value_bytes(argv[i]);
+  }
+  n += (argc-1)*nSep;
+  z = sqlite3_malloc64(n+1);
+  if( z==0 ){
+    sqlite3_result_error_nomem(context);
+    return;
+  }
+  j = 0;
+  for(i=0; i<argc; i++){
+    k = sqlite3_value_bytes(argv[i]);
+    if( k>0 ){
+      const char *v = (const char*)sqlite3_value_text(argv[i]);
+      if( ALWAYS(v!=0) ){
+        if( j>0 && nSep>0 ){
+          memcpy(&z[j], zSep, nSep);
+          j += nSep;
+        }
+        memcpy(&z[j], v, k);
+        j += k;
+      }
+    }
+  }
+  z[j] = 0;
+  assert( j<=n );
+  sqlite3_result_text64(context, z, n, sqlite3_free, SQLITE_UTF8);
+}
+
+/*
+** The CONCAT(...) function.  Generate a string result that is the
+** concatentation of all non-null arguments.
+*/
+static void concatFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  concatFuncCore(context, argc, argv, 0, "");
+}
+
+/*
+** The CONCAT_WS(separator, ...) function.
+**
+** Generate a string that is the concatenation of 2nd through the Nth
+** argument.  Use the first argument (which must be non-NULL) as the
+** separator.
+*/
+static void concatwsFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int nSep = sqlite3_value_bytes(argv[0]);
+  const char *zSep = (const char*)sqlite3_value_text(argv[0]);
+  if( zSep==0 ) return;
+  concatFuncCore(context, argc-1, argv+1, nSep, zSep);
+}
+
 
 #ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
 /*
@@ -2559,6 +2634,11 @@ void sqlite3RegisterBuiltinFunctions(void){
     FUNCTION(hex,                1, 0, 0, hexFunc          ),
     FUNCTION(unhex,              1, 0, 0, unhexFunc        ),
     FUNCTION(unhex,              2, 0, 0, unhexFunc        ),
+    FUNCTION(concat,            -1, 0, 0, concatFunc       ),
+    FUNCTION(concat,             0, 0, 0, 0                ),
+    FUNCTION(concat_ws,         -1, 0, 0, concatwsFunc     ),
+    FUNCTION(concat_ws,          0, 0, 0, 0                ),
+    FUNCTION(concat_ws,          1, 0, 0, 0                ),
     INLINE_FUNC(ifnull,          2, INLINEFUNC_coalesce, 0 ),
     VFUNCTION(random,            0, 0, 0, randomFunc       ),
     VFUNCTION(randomblob,        1, 0, 0, randomBlob       ),

test/func9.test

@@ -0,0 +1,40 @@
+# 2023-08-29
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#*************************************************************************
+#
+# Test cases for SQL newer functions
+#
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_execsql_test func9-100 {
+  SELECT concat('abc',123,null,'xyz');
+} {abc123xyz}
+do_execsql_test func9-110 {
+  SELECT typeof(concat(null));
+} {text}
+do_catchsql_test func9-120 {
+  SELECT concat();
+} {1 {wrong number of arguments to function concat()}}
+do_execsql_test func9-130 {
+  SELECT concat_ws(',',1,2,3,4,5,6,7,8,NULL,9,10,11,12);
+} {1,2,3,4,5,6,7,8,9,10,11,12}
+do_execsql_test func9-140 {
+  SELECT concat_ws(NULL,1,2,3,4,5,6,7,8,NULL,9,10,11,12);
+} {{}}
+do_catchsql_test func9-150 {
+  SELECT concat_ws();
+} {1 {wrong number of arguments to function concat_ws()}}
+do_catchsql_test func9-160 {
+  SELECT concat_ws(',');
+} {1 {wrong number of arguments to function concat_ws()}}
+
+
+finish_test