From 8f2485a57b7e08c916738fbed927d4bc65b98542 Mon Sep 17 00:00:00 2001
From: mohs8421 <thoma.kosel@gmx.de>
Date: Tue, 16 May 2023 23:47:50 +0200
Subject: [PATCH 1/2] Addressing the issue mentioned here:
 https://github.com/SeaQL/sea-orm/discussions/1620 The to use the typed
 builder is good, but in the given case it is better to ensure the query
 cannot fail by providing a name, where it is needed.

---
 src/backend/mysql/index.rs | 22 ++++++++++++----------
 src/index/create.rs        | 10 ++++++++++
 tests/mysql/index.rs       | 12 ++++++++++++
 3 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/src/backend/mysql/index.rs b/src/backend/mysql/index.rs
index 207a300f9..cd2213415 100644
--- a/src/backend/mysql/index.rs
+++ b/src/backend/mysql/index.rs
@@ -1,5 +1,7 @@
 use super::*;
 
+const MYSQL_IDENTIFIER_NAME_MAX_LENGTH: usize = 64;
+
 impl IndexBuilder for MysqlQueryBuilder {
     fn prepare_table_index_expression(
         &self,
@@ -37,16 +39,16 @@ impl IndexBuilder for MysqlQueryBuilder {
         self.prepare_index_prefix(create, sql);
         write!(sql, "INDEX ").unwrap();
 
-        if let Some(name) = &create.index.name {
-            write!(
-                sql,
-                "{}{}{}",
-                self.quote().left(),
-                name,
-                self.quote().right()
-            )
-            .unwrap();
-        }
+        let mut name = create.get_name();
+        name.truncate(MYSQL_IDENTIFIER_NAME_MAX_LENGTH);
+        write!(
+            sql,
+            "{}{}{}",
+            self.quote().left(),
+            name,
+            self.quote().right()
+        )
+        .unwrap();
 
         write!(sql, " ON ").unwrap();
         if let Some(table) = &create.table {
diff --git a/src/index/create.rs b/src/index/create.rs
index ce094d4df..1d970933a 100644
--- a/src/index/create.rs
+++ b/src/index/create.rs
@@ -229,6 +229,16 @@ impl IndexCreateStatement {
         &self.index
     }
 
+    pub(crate) fn get_name(&self) -> String {
+        if let Some(name) = self.index.name.clone() {
+            return name;
+        }
+        let prefix = if self.is_primary_key() {
+            "pri"
+        } else if self.is_unique_key() { "uni" } else { "idx" };
+        format!("{}-{}", prefix, self.index.get_column_names().join("-"))
+    }
+
     pub fn take(&mut self) -> Self {
         Self {
             table: self.table.take(),
diff --git a/tests/mysql/index.rs b/tests/mysql/index.rs
index 4c7b8d462..6e0e18014 100644
--- a/tests/mysql/index.rs
+++ b/tests/mysql/index.rs
@@ -53,6 +53,18 @@ fn create_4() {
     );
 }
 
+#[test]
+fn create_without_name() {
+    assert_eq!(
+        Index::create()
+            .index_type(IndexType::Hash)
+            .table(Glyph::Table)
+            .col(Glyph::Image)
+            .to_string(MysqlQueryBuilder),
+        "CREATE INDEX `idx-image` ON `glyph` (`image`) USING HASH"
+    );
+}
+
 #[test]
 fn drop_1() {
     assert_eq!(

From 021f99cd680b2bb895775024151537d3f0fa22c9 Mon Sep 17 00:00:00 2001
From: mohs8421 <thomas.kosel@gmx.de>
Date: Wed, 17 May 2023 09:37:25 +0200
Subject: [PATCH 2/2] Fixing format

---
 src/index/create.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/index/create.rs b/src/index/create.rs
index 1d970933a..6f0f6bbfa 100644
--- a/src/index/create.rs
+++ b/src/index/create.rs
@@ -235,7 +235,11 @@ impl IndexCreateStatement {
         }
         let prefix = if self.is_primary_key() {
             "pri"
-        } else if self.is_unique_key() { "uni" } else { "idx" };
+        } else if self.is_unique_key() {
+            "uni"
+        } else {
+            "idx"
+        };
         format!("{}-{}", prefix, self.index.get_column_names().join("-"))
     }