refactor find_eq_db_table to util::find_eq_filter

src/query/storages/system/src/columns_table.rs

@@ -24,7 +24,6 @@ use common_expression::infer_table_schema;
 use common_expression::types::StringType;
 use common_expression::utils::FromData;
 use common_expression::DataBlock;
-use common_expression::Expr;
 use common_expression::Scalar;
 use common_expression::TableDataType;
 use common_expression::TableField;
@@ -39,6 +38,7 @@ use common_storages_view::view_table::VIEW_ENGINE;
 
 use crate::table::AsyncOneBlockSystemTable;
 use crate::table::AsyncSystemTable;
+use crate::util::find_eq_db_table;
 
 pub struct ColumnsTable {
     table_info: TableInfo,
@@ -219,28 +219,3 @@ impl ColumnsTable {
         Ok(rows)
     }
 }
-
-pub fn find_eq_db_table(expr: &Expr<String>, visitor: &mut impl FnMut(&str, &Scalar)) {
-    match expr {
-        Expr::Constant { .. } | Expr::ColumnRef { .. } => {}
-        Expr::Cast { expr, .. } => find_eq_db_table(expr, visitor),
-        Expr::FunctionCall { function, args, .. } => {
-            if function.signature.name == "eq" {
-                match args.as_slice() {
-                    [Expr::ColumnRef { id, .. }, Expr::Constant { scalar, .. }]
-                    | [Expr::Constant { scalar, .. }, Expr::ColumnRef { id, .. }] => {
-                        visitor(id, scalar);
-                    }
-                    _ => {}
-                }
-            } else if function.signature.name == "and_filters" {
-                // only support this:
-                // 1. where xx and xx and xx
-                // 2. filter: Column `table`, Column `database`
-                for arg in args {
-                    find_eq_db_table(arg, visitor)
-                }
-            }
-        }
-    }
-}

src/query/storages/system/src/lib.rs

@@ -45,6 +45,7 @@ mod table_functions_table;
 mod tables_table;
 mod tracing_table;
 mod users_table;
+mod util;
 
 pub use build_options_table::BuildOptionsTable;
 pub use caches_table::CachesTable;

src/query/storages/system/src/tables_table.rs

@@ -25,7 +25,6 @@ use common_expression::types::NumberDataType;
 use common_expression::types::StringType;
 use common_expression::utils::FromData;
 use common_expression::DataBlock;
-use common_expression::Expr;
 use common_expression::FromOptData;
 use common_expression::Scalar;
 use common_expression::TableDataType;
@@ -39,6 +38,7 @@ use common_meta_app::schema::TableMeta;
 
 use crate::table::AsyncOneBlockSystemTable;
 use crate::table::AsyncSystemTable;
+use crate::util::find_eq_db_table;
 
 pub struct TablesTable<const WITH_HISTORY: bool> {
     table_info: TableInfo,
@@ -117,7 +117,7 @@ where TablesTable<T>: HistoryAware
                 let mut db_name = Vec::new();
                 if let Some(filter) = &push_downs.filter {
                     let expr = filter.as_expr(&BUILTIN_FUNCTIONS);
-                    find_eq_db_database(&expr, &mut |col_name, scalar| {
+                    find_eq_db_table(&expr, &mut |col_name, scalar| {
                         if col_name == "database" {
                             if let Scalar::String(s) = scalar {
                                 if let Ok(database) = String::from_utf8(s.clone()) {
@@ -310,28 +310,3 @@ where TablesTable<T>: HistoryAware
         AsyncOneBlockSystemTable::create(TablesTable::<T> { table_info })
     }
 }
-
-pub fn find_eq_db_database(expr: &Expr<String>, visitor: &mut impl FnMut(&str, &Scalar)) {
-    match expr {
-        Expr::Constant { .. } | Expr::ColumnRef { .. } => {}
-        Expr::Cast { expr, .. } => find_eq_db_database(expr, visitor),
-        Expr::FunctionCall { function, args, .. } => {
-            if function.signature.name == "eq" {
-                match args.as_slice() {
-                    [Expr::ColumnRef { id, .. }, Expr::Constant { scalar, .. }]
-                    | [Expr::Constant { scalar, .. }, Expr::ColumnRef { id, .. }] => {
-                        visitor(id, scalar);
-                    }
-                    _ => {}
-                }
-            } else if function.signature.name == "and_filters" {
-                // only support this:
-                // 1. where xx and xx and xx
-                // 2. filter: Column `database`
-                for arg in args {
-                    find_eq_db_database(arg, visitor)
-                }
-            }
-        }
-    }
-}

src/query/storages/system/src/util.rs

@@ -0,0 +1,41 @@
+// Copyright 2021 Datafuse Labs
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use common_expression::Expr;
+use common_expression::Scalar;
+
+pub fn find_eq_db_table(expr: &Expr<String>, visitor: &mut impl FnMut(&str, &Scalar)) {
+    match expr {
+        Expr::Constant { .. } | Expr::ColumnRef { .. } => {}
+        Expr::Cast { expr, .. } => find_eq_db_table(expr, visitor),
+        Expr::FunctionCall { function, args, .. } => {
+            if function.signature.name == "eq" {
+                match args.as_slice() {
+                    [Expr::ColumnRef { id, .. }, Expr::Constant { scalar, .. }]
+                    | [Expr::Constant { scalar, .. }, Expr::ColumnRef { id, .. }] => {
+                        visitor(id, scalar);
+                    }
+                    _ => {}
+                }
+            } else if function.signature.name == "and_filters" {
+                // only support this:
+                // 1. where xx and xx and xx
+                // 2. filter: Column `table`, Column `database`
+                for arg in args {
+                    find_eq_db_table(arg, visitor)
+                }
+            }
+        }
+    }
+}