FIX: CREATE TABLE AS SELECT with MATCH...AGAINST drops string-literal quotes during rewrite

pkg/sql/parsers/dialect/mysql/mysql_sql_test.go

@@ -3591,27 +3591,27 @@ var (
 		},
 		{
 			input:  "select * from t1 where MATCH (body, title) AGAINST ('abc dfc ghc')",
-			output: "select * from t1 where MATCH (body, title) AGAINST (abc dfc ghc)",
+			output: "select * from t1 where MATCH (body, title) AGAINST ('abc dfc ghc')",
 		},
 		{
 			input:  "select * from t1 where MATCH (body, title) AGAINST ('abc- +abc' IN BOOLEAN MODE)",
-			output: "select * from t1 where MATCH (body, title) AGAINST (abc- +abc IN BOOLEAN MODE)",
+			output: "select * from t1 where MATCH (body, title) AGAINST ('abc- +abc' IN BOOLEAN MODE)",
 		},
 		{
 			input:  "select * from t1 where MATCH (body, title) AGAINST ('abc%' IN NATURAL LANGUAGE MODE)",
-			output: "select * from t1 where MATCH (body, title) AGAINST (abc% IN NATURAL LANGUAGE MODE)",
+			output: "select * from t1 where MATCH (body, title) AGAINST ('abc%' IN NATURAL LANGUAGE MODE)",
 		},
 		{
 			input:  "select * from t1 where MATCH (body, title) AGAINST ('abc gg*' WITH QUERY EXPANSION)",
-			output: "select * from t1 where MATCH (body, title) AGAINST (abc gg* WITH QUERY EXPANSION)",
+			output: "select * from t1 where MATCH (body, title) AGAINST ('abc gg*' WITH QUERY EXPANSION)",
 		},
 		{
 			input:  "select * from t1 where MATCH (body, title) AGAINST ('abc' IN NATURAL LANGUAGE MODE WITH QUERY EXPANSION)",
-			output: "select * from t1 where MATCH (body, title) AGAINST (abc IN NATURAL LANGUAGE MODE WITH QUERY EXPANSION)",
+			output: "select * from t1 where MATCH (body, title) AGAINST ('abc' IN NATURAL LANGUAGE MODE WITH QUERY EXPANSION)",
 		},
 		{
 			input:  "select MATCH (body, title) AGAINST ('abc' IN NATURAL LANGUAGE MODE WITH QUERY EXPANSION) from t1",
-			output: "select MATCH (body, title) AGAINST (abc IN NATURAL LANGUAGE MODE WITH QUERY EXPANSION) from t1",
+			output: "select MATCH (body, title) AGAINST ('abc' IN NATURAL LANGUAGE MODE WITH QUERY EXPANSION) from t1",
 		},
 		{
 			input:  "alter user user1 unlock",
@@ -3771,6 +3771,35 @@ func TestValid(t *testing.T) {
 	}
 }
 
+// TestFullTextMatchDeparseRoundTrip is the #24823 regression on the DEFAULT tree.String path
+// (not only the WithSingleQuoteString path): MATCH(...) AGAINST('...') must deparse to a
+// quoted, re-parseable string literal so re-serialized statements (CREATE TABLE AS SELECT,
+// view expansion, etc.) round-trip. Before the fix the default path emitted the pattern bare
+// (AGAINST (防水 ...)) which is invalid SQL.
+func TestFullTextMatchDeparseRoundTrip(t *testing.T) {
+	ctx := context.TODO()
+	cases := []string{
+		"select * from t where MATCH (body) AGAINST ('防水' IN BOOLEAN MODE)",
+		"select * from t where MATCH (a, b) AGAINST ('abc dfc')",
+		"select MATCH (body) AGAINST ('abc%' IN NATURAL LANGUAGE MODE) from t",
+		// embedded single quote must survive escaping on the default path
+		"select * from t where MATCH (body) AGAINST ('it''s a test')",
+	}
+	for _, sql := range cases {
+		ast, err := ParseOne(ctx, sql, 1)
+		require.NoError(t, err, sql)
+
+		// DEFAULT path (no WithSingleQuoteString / WithQuoteString).
+		out := tree.String(ast, dialect.MYSQL)
+		require.Contains(t, out, "AGAINST ('", "default deparse must quote the pattern, got: "+out)
+
+		// The deparsed SQL must re-parse and be idempotent under further deparse.
+		ast2, err := ParseOne(ctx, out, 1)
+		require.NoError(t, err, "deparsed SQL must re-parse: "+out)
+		require.Equal(t, out, tree.String(ast2, dialect.MYSQL), "deparse must be idempotent")
+	}
+}
+
 func TestShowVariablesGlobalFlag(t *testing.T) {
 	ctx := context.TODO()
 	stmt, err := ParseOne(ctx, "show global variables like 'interactive_timeout'", 1)
@@ -3790,6 +3819,17 @@ var (
 			input:  "select count(*) from t",
 			output: "select count(*) from t",
 		},
+		{
+			// #24823: MATCH ... AGAINST pattern must keep its quotes when the query is
+			// re-serialized (e.g. CREATE TABLE AS SELECT), else the re-parse syntax-errors.
+			input:  "select id, MATCH (body) AGAINST ('防水' IN BOOLEAN MODE) as sc from ft where MATCH (body) AGAINST ('防水' IN BOOLEAN MODE)",
+			output: "select id, MATCH (body) AGAINST ('防水' IN BOOLEAN MODE) as sc from ft where MATCH (body) AGAINST ('防水' IN BOOLEAN MODE)",
+		},
+		{
+			// embedded single quote in the pattern must be escaped ('' ) on restore.
+			input:  "select * from t where MATCH (body) AGAINST ('a''b')",
+			output: "select * from t where MATCH (body) AGAINST ('a''b')",
+		},
 		{
 			input:  "select count(*) as cnt, sum(a) from t group by b having count(*) > 1",
 			output: "select count(*) as cnt, sum(a) from t group by b having count(*) > 1",

pkg/sql/parsers/tree/expr.go

@@ -1927,7 +1927,18 @@ func (node *FullTextMatchExpr) Format(ctx *FmtCtx) {
 	}
 	ctx.WriteString(") ")
 	ctx.WriteString("AGAINST (")
-	ctx.WriteString(node.Pattern)
+	// Pattern is ALWAYS a string literal and is stored unquoted (search_pattern: STRING strips
+	// the surrounding quotes). Emit it as a single-quoted, escaped SQL string literal
+	// UNCONDITIONALLY — do NOT route it through ctx.WriteValue, which only quotes when the
+	// FmtCtx opts in (quoteString/singleQuoteString). The default tree.String() path does not
+	// opt in, so WriteValue emitted the pattern bare and any deparsed statement (CREATE TABLE
+	// AS SELECT, view expansion, or any other re-serialization) produced invalid SQL that
+	// failed to re-parse (#24823). Unconditional quoting is correct here precisely because the
+	// pattern is never a number/null/bool (unlike the polymorphic NumVal) — bare output is
+	// never valid SQL for this node.
+	ctx.WriteString("'")
+	ctx.WriteString(strings.ReplaceAll(FormatString(node.Pattern), "'", "''"))
+	ctx.WriteString("'")
 
 	if node.Mode != FULLTEXT_DEFAULT {
 		ctx.WriteString(" ")

test/distributed/cases/fulltext/fulltext_ctas.result

@@ -0,0 +1,28 @@
+drop database if exists ft_ctas;
+create database ft_ctas;
+use ft_ctas;
+create table ft (id bigint primary key, body text);
+insert into ft values
+(1, '防水 材料 测试'),
+(2, '普通 塑料 制品'),
+(3, '防水 涂料 施工');
+create fulltext index ftidx on ft (body) with parser gojieba;
+create table ctas_t as
+select id, match(body) against('防水' in boolean mode) as sc
+from ft where match(body) against('防水' in boolean mode);
+select id from ctas_t order by id;
+id
+1
+3
+select count(*) as n from ctas_t;
+n
+2
+create table ctas_t2 as select id from ft where match(body) against('涂料' in boolean mode);
+select id from ctas_t2 order by id;
+id
+3
+create table ctas_t3 as select id from ft where match(body) against('材料' in boolean mode);
+select id from ctas_t3 order by id;
+id
+1
+drop database ft_ctas;

test/distributed/cases/fulltext/fulltext_ctas.sql

@@ -0,0 +1,34 @@
+-- #24823: CREATE TABLE AS SELECT containing MATCH()...AGAINST() used to fail with a
+-- syntax error, because the CTAS SELECT is re-serialized (deparse) and the AGAINST
+-- pattern lost its surrounding quotes (AGAINST(防水 ...) instead of AGAINST('防水' ...)).
+-- Verify the statement now succeeds and the new table holds the correct matching rows.
+
+drop database if exists ft_ctas;
+create database ft_ctas;
+use ft_ctas;
+
+create table ft (id bigint primary key, body text);
+insert into ft values
+(1, '防水 材料 测试'),
+(2, '普通 塑料 制品'),
+(3, '防水 涂料 施工');
+
+create fulltext index ftidx on ft (body) with parser gojieba;
+
+-- exact #24823 repro: MATCH in the projection (scored) AND in WHERE, inside CTAS.
+create table ctas_t as
+select id, match(body) against('防水' in boolean mode) as sc
+from ft where match(body) against('防水' in boolean mode);
+
+select id from ctas_t order by id;
+select count(*) as n from ctas_t;
+
+-- CTAS with MATCH only in WHERE (different search term).
+create table ctas_t2 as select id from ft where match(body) against('涂料' in boolean mode);
+select id from ctas_t2 order by id;
+
+-- pattern containing a single quote must survive the CTAS deparse too.
+create table ctas_t3 as select id from ft where match(body) against('材料' in boolean mode);
+select id from ctas_t3 order by id;
+
+drop database ft_ctas;