Small Refactorings

src/backend/mysql/foreign_key.rs

@@ -24,7 +24,14 @@ impl ForeignKeyBuilder for MysqlQueryBuilder {
 
         write!(sql, "DROP FOREIGN KEY ").unwrap();
         if let Some(name) = &drop.foreign_key.name {
-            write!(sql, "`{name}`").unwrap();
+            write!(
+                sql,
+                "{}{}{}",
+                self.quote().left(),
+                name,
+                self.quote().right()
+            )
+            .unwrap();
         }
     }
 
@@ -48,7 +55,14 @@ impl ForeignKeyBuilder for MysqlQueryBuilder {
 
         write!(sql, "CONSTRAINT ").unwrap();
         if let Some(name) = &create.foreign_key.name {
-            write!(sql, "`{name}`").unwrap();
+            write!(
+                sql,
+                "{}{}{}",
+                self.quote().left(),
+                name,
+                self.quote().right()
+            )
+            .unwrap();
         }
         write!(sql, " FOREIGN KEY ").unwrap();
 

src/backend/mysql/query.rs

@@ -51,7 +51,6 @@ impl QueryBuilder for MysqlQueryBuilder {
         }
         if !matches!(order_expr.order, Order::Field(_)) {
             self.prepare_simple_expr(&order_expr.expr, sql);
-            write!(sql, " ").unwrap();
         }
         self.prepare_order(order_expr, sql);
     }

src/backend/postgres/foreign_key.rs

@@ -17,7 +17,14 @@ impl ForeignKeyBuilder for PostgresQueryBuilder {
 
         write!(sql, "DROP CONSTRAINT ").unwrap();
         if let Some(name) = &drop.foreign_key.name {
-            write!(sql, "\"{name}\"").unwrap();
+            write!(
+                sql,
+                "{}{}{}",
+                self.quote().left(),
+                name,
+                self.quote().right()
+            )
+            .unwrap();
         }
     }
 
@@ -41,7 +48,14 @@ impl ForeignKeyBuilder for PostgresQueryBuilder {
 
         if let Some(name) = &create.foreign_key.name {
             write!(sql, "CONSTRAINT ").unwrap();
-            write!(sql, "\"{name}\" ").unwrap();
+            write!(
+                sql,
+                "{}{}{} ",
+                self.quote().left(),
+                name,
+                self.quote().right()
+            )
+            .unwrap();
         }
 
         write!(sql, "FOREIGN KEY (").unwrap();

src/backend/postgres/query.rs

@@ -95,7 +95,6 @@ impl QueryBuilder for PostgresQueryBuilder {
     fn prepare_order_expr(&self, order_expr: &OrderExpr, sql: &mut dyn SqlWriter) {
         if !matches!(order_expr.order, Order::Field(_)) {
             self.prepare_simple_expr(&order_expr.expr, sql);
-            write!(sql, " ").unwrap();
         }
         self.prepare_order(order_expr, sql);
         match order_expr.nulls {

src/backend/query_builder.rs

@@ -845,8 +845,8 @@ pub trait QueryBuilder: QuotedBuilder + EscapeBuilder + TableRefBuilder {
     /// Translate [`Order`] into SQL statement.
     fn prepare_order(&self, order_expr: &OrderExpr, sql: &mut dyn SqlWriter) {
         match &order_expr.order {
-            Order::Asc => write!(sql, "ASC").unwrap(),
-            Order::Desc => write!(sql, "DESC").unwrap(),
+            Order::Asc => write!(sql, " ASC").unwrap(),
+            Order::Desc => write!(sql, " DESC").unwrap(),
             Order::Field(values) => self.prepare_field_order(order_expr, values, sql),
         }
     }

src/backend/sqlite/foreign_key.rs

@@ -20,7 +20,14 @@ impl ForeignKeyBuilder for SqliteQueryBuilder {
 
         write!(sql, "DROP FOREIGN KEY ").unwrap();
         if let Some(name) = &drop.foreign_key.name {
-            write!(sql, "`{name}`").unwrap();
+            write!(
+                sql,
+                "{}{}{}",
+                self.quote().left(),
+                name,
+                self.quote().right()
+            )
+            .unwrap();
         }
     }
 

src/backend/sqlite/query.rs

@@ -62,7 +62,6 @@ impl QueryBuilder for SqliteQueryBuilder {
     fn prepare_order_expr(&self, order_expr: &OrderExpr, sql: &mut dyn SqlWriter) {
         if !matches!(order_expr.order, Order::Field(_)) {
             self.prepare_simple_expr(&order_expr.expr, sql);
-            write!(sql, " ").unwrap();
         }
         self.prepare_order(order_expr, sql);
         match order_expr.nulls {

src/expr.rs

@@ -1095,7 +1095,7 @@ impl Expr {
     /// let query = Query::select()
     ///     .columns([Char::Character, Char::SizeW, Char::SizeH])
     ///     .from(Char::Table)
-    ///     .and_where(Expr::col((Char::Table, Char::Character)).like(LikeExpr::str(r"|_Our|_").escape('|')))
+    ///     .and_where(Expr::col((Char::Table, Char::Character)).like(LikeExpr::new(r"|_Our|_").escape('|')))
     ///     .to_owned();
     ///
     /// assert_eq!(

tests/mysql/query.rs

@@ -995,7 +995,7 @@ fn select_58() {
         Query::select()
             .column(Char::Character)
             .from(Char::Table)
-            .and_where(Expr::col(Char::Character).like(LikeExpr::str("A").escape('\\')))
+            .and_where(Expr::col(Char::Character).like(LikeExpr::new("A").escape('\\')))
             .build(MysqlQueryBuilder),
         (
             r#"SELECT `character` FROM `character` WHERE `character` LIKE ? ESCAPE '\\'"#

tests/postgres/query.rs

@@ -1058,7 +1058,7 @@ fn select_61() {
         Query::select()
             .column(Char::Character)
             .from(Char::Table)
-            .and_where(Expr::col(Char::Character).like(LikeExpr::str("A").escape('\\')))
+            .and_where(Expr::col(Char::Character).like(LikeExpr::new("A").escape('\\')))
             .build(PostgresQueryBuilder),
         (
             r#"SELECT "character" FROM "character" WHERE "character" LIKE $1 ESCAPE E'\\'"#

tests/sqlite/query.rs

@@ -983,7 +983,7 @@ fn select_58() {
         Query::select()
             .column(Char::Character)
             .from(Char::Table)
-            .and_where(Expr::col(Char::Character).like(LikeExpr::str("A").escape('\\')))
+            .and_where(Expr::col(Char::Character).like(LikeExpr::new("A").escape('\\')))
             .build(SqliteQueryBuilder),
         (
             r#"SELECT "character" FROM "character" WHERE "character" LIKE ? ESCAPE '\'"#.to_owned(),