# Code completion > **TL;DR** > Configure: Settings (`Ctrl+Alt+S` (Windows), `⌘ Comma` (macOS), `⌘ Comma` (IntelliJ IDEA Classic (macOS)), `⌘ Comma` (macOS System Shortcuts), `Ctrl+Alt+S` (XWin), `Ctrl+Alt+S` (GNOME), `Ctrl+Alt+S` (KDE), `Ctrl+Alt+S` (Emacs), `Ctrl+Alt+S` (Sublime Text), `⌘ Comma` (Sublime Text (macOS)), `⌘ Comma` (Xcode), `Ctrl+Alt+S` (Visual Studio), `⌘ Comma` (Visual Studio (macOS)), `Ctrl+Alt+S` (ReSharper), `⌘ Comma` (ReSharper (macOS)), `Ctrl+Alt+S` (QtCreator), `⌘ Comma` (QtCreator (macOS)), `Ctrl+Alt+S` (NetBeans), `Ctrl+Alt+S` (Eclipse), `⌘ Comma` (Eclipse (macOS))) `| Editor | General | Code Completion | Popup` > > > > For automatic completion, enable Show suggestions as you type > > > > Basic completion: `Ctrl+Space` (Windows), `⌃ Space` (macOS), `⌃ Space` (IntelliJ IDEA Classic (macOS)), `⌃ Space` (macOS System Shortcuts), `Ctrl+Space` (XWin), `Ctrl+Space` (GNOME), `Ctrl+Space` (KDE), `Alt+/` (Emacs), `Ctrl+Space` (Sublime Text), `⌃ Space` (Sublime Text (macOS)), `⌃ Space` (Xcode), `Ctrl+Space` (Visual Studio), `⌃ Space` (Visual Studio (macOS)), `Ctrl+Space` (ReSharper), `⌃ Space` (ReSharper (macOS)), `Ctrl+Space` (QtCreator), `⌃ Space` (QtCreator (macOS)), `Ctrl+Space` (NetBeans), `Ctrl+Space` (Eclipse), `⌃ Space` (Eclipse (macOS)) > > > > To reject all suggestions, press `Escape` (Windows), `⎋` (macOS), `⎋` (IntelliJ IDEA Classic (macOS)), `⎋` (macOS System Shortcuts), `Escape` (XWin), `Escape` (GNOME), `Escape` (KDE), `Escape, Escape` (Emacs), `Escape` (Sublime Text), `⎋` (Sublime Text (macOS)), `⎋` (Xcode), `Escape` (Visual Studio), `⎋` (Visual Studio (macOS)), `Escape` (ReSharper), `⎋` (ReSharper (macOS)), `Escape` (QtCreator), `⎋` (QtCreator (macOS)), `Escape` (NetBeans), `Escape` (Eclipse), `⎋` (Eclipse (macOS)) Basic code completion helps you complete names, types, and keywords within the visibility scope. CLion analyzes the context and suggests the choices that are reachable from the current caret position. Suggestions also include [Live templates](using-live-templates.html). Completion is available for a non-English keyboard layout. Procedure: Invoke basic completion * By default, CLion displays the code completion popup automatically as you type. Alternatively, you can press `Ctrl+Space` (Windows), `⌃ Space` (macOS), `⌃ Space` (IntelliJ IDEA Classic (macOS)), `⌃ Space` (macOS System Shortcuts), `Ctrl+Space` (XWin), `Ctrl+Space` (GNOME), `Ctrl+Space` (KDE), `Alt+/` (Emacs), `Ctrl+Space` (Sublime Text), `⌃ Space` (Sublime Text (macOS)), `⌃ Space` (Xcode), `Ctrl+Space` (Visual Studio), `⌃ Space` (Visual Studio (macOS)), `Ctrl+Space` (ReSharper), `⌃ Space` (ReSharper (macOS)), `Ctrl+Space` (QtCreator), `⌃ Space` (QtCreator (macOS)), `Ctrl+Space` (NetBeans), `Ctrl+Space` (Eclipse), `⌃ Space` (Eclipse (macOS)) or select `Code | Code Completion | Basic` from the main menu. ![Basis completion popup](https://resources.jetbrains.com/help/img/idea/2026.2/cl_completion_basic.png) * * Code completion is available for [custom file types](creating-and-registering-file-types.html). However, CLion does not recognize the structure of such files and suggests options regardless of whether they are appropriate in the current context. Procedure: Accept a suggestion from the list * Press `Enter` (Windows), `⏎` (macOS), `⏎` (IntelliJ IDEA Classic (macOS)), `⏎` (macOS System Shortcuts), `Enter` (XWin), `Enter` (GNOME), `Enter` (KDE), `Enter` (Emacs), `Enter` (Sublime Text), `⏎` (Sublime Text (macOS)), `⏎` (Xcode), `Enter` (Visual Studio), `⏎` (Visual Studio (macOS)), `Enter` (ReSharper), `⏎` (ReSharper (macOS)), `Enter` (QtCreator), `⏎` (QtCreator (macOS)), `Enter` (NetBeans), `Enter` (Eclipse), `⏎` (Eclipse (macOS)) or double-click the relevant list item to insert it to the left of the caret. * Press `Tab` (Windows), `⇥` (macOS), `⇥` (IntelliJ IDEA Classic (macOS)), `⇥` (macOS System Shortcuts), `Tab` (XWin), `Tab` (GNOME), `Tab` (KDE), `Tab` (Emacs), `Tab` (Sublime Text), `⇥` (Sublime Text (macOS)), `⇥` (Xcode), `Tab` (Visual Studio), `⇥` (Visual Studio (macOS)), `Tab` (ReSharper), `⇥` (ReSharper (macOS)), `Tab` (QtCreator), `⇥` (QtCreator (macOS)), `Tab` (NetBeans), `Tab` (Eclipse), `⇥` (Eclipse (macOS)) to replace the characters to the right from the caret. * Use `Ctrl+Shift+Enter` (Windows), `⌘ ⇧ ⏎` (macOS), `⌘ ⇧ ⏎` (IntelliJ IDEA Classic (macOS)), `⌘ ⇧ ⏎` (macOS System Shortcuts), `Ctrl+Shift+Enter` (XWin), `Ctrl+Shift+Enter` (GNOME), `Ctrl+Shift+Enter` (KDE), `Ctrl+Shift+Enter` (Emacs), `Ctrl+Shift+Enter` (Sublime Text), `Ctrl+Shift+Enter` (Sublime Text (macOS)), `⌘ ⇧ ⏎` (Xcode), `Ctrl+Shift+Enter` (Visual Studio), `⌘ ⇧ ⏎` (Visual Studio (macOS)), `Ctrl+Shift+Enter` (ReSharper), `⌘ ⇧ ⏎` (ReSharper (macOS)), `Ctrl+Shift+Enter` (QtCreator), `Ctrl+Shift+Enter` (QtCreator (macOS)), `Ctrl+Shift+Enter` (NetBeans), `Ctrl+Shift+Enter` (Eclipse), `⌘ ⇧ ⏎` (Eclipse (macOS)) to make the current code construct syntactically correct (balance parentheses, add missing braces and semicolons, and so on). * Use specific keys and custom characters to accept the selected completion suggestion. To enable these features, go to the Editor | General | Code Completion | Popup settings page `Ctrl+Alt+S` (Windows), `⌘ Comma` (macOS), `⌘ Comma` (IntelliJ IDEA Classic (macOS)), `⌘ Comma` (macOS System Shortcuts), `Ctrl+Alt+S` (XWin), `Ctrl+Alt+S` (GNOME), `Ctrl+Alt+S` (KDE), `Ctrl+Alt+S` (Emacs), `Ctrl+Alt+S` (Sublime Text), `⌘ Comma` (Sublime Text (macOS)), `⌘ Comma` (Xcode), `Ctrl+Alt+S` (Visual Studio), `⌘ Comma` (Visual Studio (macOS)), `Ctrl+Alt+S` (ReSharper), `⌘ Comma` (ReSharper (macOS)), `Ctrl+Alt+S` (QtCreator), `⌘ Comma` (QtCreator (macOS)), `Ctrl+Alt+S` (NetBeans), `Ctrl+Alt+S` (Eclipse), `⌘ Comma` (Eclipse (macOS)) and do the following: 1. To use specific keys, select the Insert selected suggestion by pressing space, dot, or other context-dependent keys checkbox. These keys depend on the language, your context, and so on. 2. To also use custom characters, enter the characters into the Additional characters to accept the completion field. > **Note:** > While this setting helps you save time, turning it on may result in items being inserted accidentally. ## Machine learning-assisted completion ranking CLion allows you to prioritize completion suggestions based on choices that other users made in similar situations. The ML completion mechanism does not add any new elements but orders the elements retrieved from code. Data is not exposed anywhere; it is collected locally. Procedure: Enable ML completion ranking 1. Press `Ctrl+Alt+S` (Windows), `⌘ Comma` (macOS), `⌘ Comma` (IntelliJ IDEA Classic (macOS)), `⌘ Comma` (macOS System Shortcuts), `Ctrl+Alt+S` (XWin), `Ctrl+Alt+S` (GNOME), `Ctrl+Alt+S` (KDE), `Ctrl+Alt+S` (Emacs), `Ctrl+Alt+S` (Sublime Text), `⌘ Comma` (Sublime Text (macOS)), `⌘ Comma` (Xcode), `Ctrl+Alt+S` (Visual Studio), `⌘ Comma` (Visual Studio (macOS)), `Ctrl+Alt+S` (ReSharper), `⌘ Comma` (ReSharper (macOS)), `Ctrl+Alt+S` (QtCreator), `⌘ Comma` (QtCreator (macOS)), `Ctrl+Alt+S` (NetBeans), `Ctrl+Alt+S` (Eclipse), `⌘ Comma` (Eclipse (macOS)) to open settings and select Editor | General | Code Completion | Popup. 2. Under Sort Suggestions with ML, enable the Sort completion suggestions based on machine learning option and select the languages for which you want to use the ML completion. ![ML-assisted completion settings](https://resources.jetbrains.com/help/img/idea/2026.2/cl_ML_assisted_completion_settings.png) Procedure: Enable relevance markers 1. Press `Ctrl+Alt+S` (Windows), `⌘ Comma` (macOS), `⌘ Comma` (IntelliJ IDEA Classic (macOS)), `⌘ Comma` (macOS System Shortcuts), `Ctrl+Alt+S` (XWin), `Ctrl+Alt+S` (GNOME), `Ctrl+Alt+S` (KDE), `Ctrl+Alt+S` (Emacs), `Ctrl+Alt+S` (Sublime Text), `⌘ Comma` (Sublime Text (macOS)), `⌘ Comma` (Xcode), `Ctrl+Alt+S` (Visual Studio), `⌘ Comma` (Visual Studio (macOS)), `Ctrl+Alt+S` (ReSharper), `⌘ Comma` (ReSharper (macOS)), `Ctrl+Alt+S` (QtCreator), `⌘ Comma` (QtCreator (macOS)), `Ctrl+Alt+S` (NetBeans), `Ctrl+Alt+S` (Eclipse), `⌘ Comma` (Eclipse (macOS)) to open settings and select Editor | General | Code Completion | Popup. 2. Enable the following options: ![ML completion markers settings](https://resources.jetbrains.com/help/img/idea/2026.2/cl_ml_completion_markers_settings.png) * Mark position changes in the completion popup: use the ![Machine Learning ranking Up](https://resources.jetbrains.com/help/img/idea/2026.2/completionMlRanking.icons.proposalUp.svg) and ![Machine Learning ranking Down](https://resources.jetbrains.com/help/img/idea/2026.2/completionMlRanking.icons.proposalDown.svg) icons to indicate whether the relevance of a suggestion is increasing or decreasing and therefore the suggestion has moved up or down the suggestion list. * Mark the most relevant item in the completion popup: use the ![ML relevant proposal](https://resources.jetbrains.com/help/img/idea/2026.2/completionMlRanking.icons.relevantProposal.svg) icon to indicate the most suitable suggestion on the list. The suggestion list will look as follows with the icons marking reordered and the most relevant items. ![ML-assisted completion with markers](https://resources.jetbrains.com/help/img/idea/2026.2/cl_ml_assisted_completion_markers.png) ## Code completion settings To configure code completion options, go to the Editor | General | Code Completion | Popup settings page `Ctrl+Alt+S` (Windows), `⌘ Comma` (macOS), `⌘ Comma` (IntelliJ IDEA Classic (macOS)), `⌘ Comma` (macOS System Shortcuts), `Ctrl+Alt+S` (XWin), `Ctrl+Alt+S` (GNOME), `Ctrl+Alt+S` (KDE), `Ctrl+Alt+S` (Emacs), `Ctrl+Alt+S` (Sublime Text), `⌘ Comma` (Sublime Text (macOS)), `⌘ Comma` (Xcode), `Ctrl+Alt+S` (Visual Studio), `⌘ Comma` (Visual Studio (macOS)), `Ctrl+Alt+S` (ReSharper), `⌘ Comma` (ReSharper (macOS)), `Ctrl+Alt+S` (QtCreator), `⌘ Comma` (QtCreator (macOS)), `Ctrl+Alt+S` (NetBeans), `Ctrl+Alt+S` (Eclipse), `⌘ Comma` (Eclipse (macOS)) . You can choose the following settings: | Item | Description | | --- | --- | | Match case | Select if you want the letter case to be taken into account for completion suggestions. Choose whether you want to match the case for the first letter or for all letters. | | Automatically insert single suggestions for | Automatically complete code if there is only one suggestion for basic and smart type-matching completion. | | Sort suggestions alphabetically | Select if you want to sort items in the suggestion list in the alphabetical order instead of sorting them by relevance. You can change this behavior at any time by clicking ![](https://resources.jetbrains.com/help/img/idea/2026.2/app.actions.more.svg) in the suggestion list and toggling the Sort by Name option. | | Show suggestions as you type | Select if you want the suggestion list to be invoked automatically, without having to call completion explicitly. This option is enabled by default. | | Show the documentation popup in | Automatically [show a popup](#doc-in-completion) for each item in the suggestion list with the documentation for the class, method, or field currently highlighted in the lookup list. When this option is disabled, press `Ctrl+Q` (Windows), `F1` (macOS), `⌃ J` (IntelliJ IDEA Classic (macOS)), `⌘ I` (macOS System Shortcuts), `Ctrl+Q` (XWin), `Ctrl+Q` (GNOME), `Ctrl+Q` (KDE), `Ctrl+Q` (Emacs), `Ctrl+Q` (Sublime Text), `Ctrl+Q` (Sublime Text (macOS)), `⌘ ⌃ ⇧ /` (Xcode), `Ctrl+K, I` (Visual Studio), `⌘ K, I` (Visual Studio (macOS)), `Ctrl+Q` (ReSharper), `⌃ Q` (ReSharper (macOS)), `Ctrl+Q` (QtCreator), `Ctrl+Q` (QtCreator (macOS)), `Ctrl+Q` (NetBeans), `Alt+Middle-Click` (Eclipse), `⌥ Middle-Click` (Eclipse (macOS)) to display documentation for elements. In the field to the right, specify the delay (in milliseconds), after which the popup should appear. | | Insert parentheses automatically when applicable | If this option is enabled, CLion automatically inserts a pair of opening and closing parentheseswhen you complete a function/method. Clear the checkbox to suppress inserting parentheses automatically. If you use an opening parentheses `(` instead of `Enter` (Windows), `⏎` (macOS), `⏎` (IntelliJ IDEA Classic (macOS)), `⏎` (macOS System Shortcuts), `Enter` (XWin), `Enter` (GNOME), `Enter` (KDE), `Enter` (Emacs), `Enter` (Sublime Text), `⏎` (Sublime Text (macOS)), `⏎` (Xcode), `Enter` (Visual Studio), `⏎` (Visual Studio (macOS)), `Enter` (ReSharper), `⏎` (ReSharper (macOS)), `Enter` (QtCreator), `⏎` (QtCreator (macOS)), `Enter` (NetBeans), `Enter` (Eclipse), `⏎` (Eclipse (macOS)) to apply the selected item from a completion list, parentheses will be inserted automatically no matter whether the option is turned on or off. To use an opening parentheses `(` instead of `Enter` (Windows), `⏎` (macOS), `⏎` (IntelliJ IDEA Classic (macOS)), `⏎` (macOS System Shortcuts), `Enter` (XWin), `Enter` (GNOME), `Enter` (KDE), `Enter` (Emacs), `Enter` (Sublime Text), `⏎` (Sublime Text (macOS)), `⏎` (Xcode), `Enter` (Visual Studio), `⏎` (Visual Studio (macOS)), `Enter` (ReSharper), `⏎` (ReSharper (macOS)), `Enter` (QtCreator), `⏎` (QtCreator (macOS)), `Enter` (NetBeans), `Enter` (Eclipse), `⏎` (Eclipse (macOS)) to apply the selected item from a completion list, open the Settings dialog (`Ctrl+Alt+S` (Windows), `⌘ Comma` (macOS), `⌘ Comma` (IntelliJ IDEA Classic (macOS)), `⌘ Comma` (macOS System Shortcuts), `Ctrl+Alt+S` (XWin), `Ctrl+Alt+S` (GNOME), `Ctrl+Alt+S` (KDE), `Ctrl+Alt+S` (Emacs), `Ctrl+Alt+S` (Sublime Text), `⌘ Comma` (Sublime Text (macOS)), `⌘ Comma` (Xcode), `Ctrl+Alt+S` (Visual Studio), `⌘ Comma` (Visual Studio (macOS)), `Ctrl+Alt+S` (ReSharper), `⌘ Comma` (ReSharper (macOS)), `Ctrl+Alt+S` (QtCreator), `⌘ Comma` (QtCreator (macOS)), `Ctrl+Alt+S` (NetBeans), `Ctrl+Alt+S` (Eclipse), `⌘ Comma` (Eclipse (macOS))), go to `Editor \| General \| Code Completion \| Popup`, and select the Insert selected suggestion by pressing space, dot, or other context-dependent keys checkbox. For more information, refer to [Use specific keys to insert suggestions](#shortcuts_to_accept_suggestions). | | Show import items in basic completion | When a symbol that you want to use is not imported in the current file with the corresponding `#include`, but it is defined in the standard libraries or elsewhere in your solution, you can press `Ctrl+Alt+Space` (Windows), `⌃ ⌥ Space` (macOS), `⌃ ⌥ Space` (IntelliJ IDEA Classic (macOS)), `⌃ ⌥ Space` (macOS System Shortcuts), `Ctrl+Alt+Space` (XWin), `Ctrl+Alt+Space` (GNOME), `Ctrl+Alt+Space` (KDE), `Ctrl+Alt+Space` (Emacs), `Ctrl+Alt+Space` (Sublime Text), `⌃ ⌥ Space` (Sublime Text (macOS)), `⌃ ⌥ Space` (Xcode), `Alt+Shift+Space` (Visual Studio), `⌥ ⇧ Space` (Visual Studio (macOS)), `Ctrl+Alt+Space` (ReSharper), `⌃ ⌥ Space` (ReSharper (macOS)), `Ctrl+Alt+Space` (QtCreator), `⌃ ⌥ Space` (QtCreator (macOS)), `Ctrl+Alt+Space` (NetBeans), `Ctrl+Alt+Space` (Eclipse), `⌃ ⌥ Space` (Eclipse (macOS)) to quickly find this symbol in completion suggestions. You can use this option to include import symbol suggestions into the suggestion lists of automatic and basic completion. | | Behavior of import items | Configure the import completion behavior to always insert an `include` directive or show a menu with an option to add a forward declaration. | | Show free functions in members completion | One common C++ coding practice is to prefer non-member non-friend functions to member functions. This is a great way to increase encapsulation and keep class interfaces as minimal as possible. When you type a dot `.` or an arrow `->` after an expression, free functions that accept the expression as the first parameter will be suggested in the completion list after member functions. Clear this checkbox if you do not want to have free functions in the completion suggestions. | | Machine Learning-Assisted Completion | | | Sort completion suggestions based on machine learning | Select this option if you want to use machine learning models to rank the most suitable items higher in the suggestion list. Select the languages for which you want to enable suggestions based on machine learning. | | Mark position changes in the completion popup | Use the ![Machine Learning ranking Up](https://resources.jetbrains.com/help/img/idea/2026.2/completionMlRanking.icons.proposalUp.svg) and ![Machine Learning ranking Down](https://resources.jetbrains.com/help/img/idea/2026.2/completionMlRanking.icons.proposalDown.svg) icons to indicate whether the relevance of a suggestion is increasing or decreasing and therefore the suggestion has moved up or down the suggestion list. | | Mark the most relevant item in the completion popup | Use the ![ML relevant proposal](https://resources.jetbrains.com/help/img/idea/2026.2/completionMlRanking.icons.relevantProposal.svg) icon to indicate the most suitable suggestion on the list. | | JavaScript | | Only type-based completion | By default, CLion suggests completion for symbols regardless of their types. With this approach, in complicated cases the list shows multiple completion variants. To make completion more precise, select this option. The completion list will strongly depend on the CLion inference. As a result, the list may remain empty in case of poor inference. | | Suggest items with optional chaining for nullable types | By default, CLion suggests completion for symbols with the [optional chaining operator (?)](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining). Clear this checkbox to suppress this behavior. | | Expand method bodies in completion for overrides | By default, when you want to override a method from the parent class or interface and select this method from the list of completion suggestions, CLion automatically adds parameters, generates a `super()` call, and adds the type information, if possible. Clear this checkbox to suppress automatic generation of method bodies for overrides during completion. | | Completion of names | * Suggest variable and parameter names: By default, the checkbox is cleared. When it is selected, CLion suggests names for new class fields, variables, and parameters during their declaration. These suggestions are based on the names of classes, types, and interfaces that are defined in your project, in the libraries you are using, and in standard APIs. * Suggest names for class fields The option is turned off by default. * Add type annotations for suggested parameter names: Select this checkbox to supply each completion suggestion with information on its type. The checkbox is available only when the Suggest variable and parameter names checkbox is selected. | | Parameter Info | | Show the parameter info popup in | Select this checkbox to have CLion automatically show a popup with all available method signatures when an opening bracket is typed in the editor, or a method is selected from the suggestion list. In the text field to the right, specify the delay (in milliseconds) after when the popup window should appear. If this checkbox is not selected, use `Ctrl+P` (Windows), `⌘ P` (macOS), `⌘ P` (IntelliJ IDEA Classic (macOS)), `⌘ P` (macOS System Shortcuts), `Ctrl+P` (XWin), `Ctrl+P` (GNOME), `Ctrl+P` (KDE), `Alt+Shift+P` (Emacs), `Ctrl+P` (Sublime Text), `Ctrl+P` (Sublime Text (macOS)), `⌘ ⇧ P` (Xcode), `Ctrl+Shift+Space` (Visual Studio), `⌘ P` (Visual Studio (macOS)), `Ctrl+P` (ReSharper), `⌘ P` (ReSharper (macOS)), `Ctrl+P` (QtCreator), `Ctrl+P` (QtCreator (macOS)), `Ctrl+P` (NetBeans), `Ctrl+P` (Eclipse), `⌃ ⇧ Space` (Eclipse (macOS)) to show parameter info. | | Show full method signatures | If this checkbox is selected, the parameter info displays full signatures, including method name and returned type. | | SQL | | Suggest objects from | Select where the objects are suggested from: * The current search path only: only the schema selected for a console. For more information about selecting a schema, refer to [Set the default schema for a query console](schemas.html#set_default_schema_query_console). * The current scope: the schema currently selected for a console and system schemas (for example, `pg_catalog` in PostgreSQL. * All available schemas: all introspected schemas. The current path only: ![Objects suggested from the current path only](https://resources.jetbrains.com/help/img/idea/2026.2/suggest_objects_from_search_path.png) The current scope: ![Objects suggested from all the schemas](https://resources.jetbrains.com/help/img/idea/2026.2/suggest_objects_from_the_current_scope.png) All schemas: ![Objects suggested from all the schemas](https://resources.jetbrains.com/help/img/idea/2026.2/suggest_objects_from_all_schemas.png) | | Qualify objects with | Select when to qualify the objects with databases, schemas, tables and views, and aliases of tables and views. * Always: the qualified object names are always used, for example `.`. * On collisions: the qualified object name is used only if the short name is ambiguous, for example, when there is the object with the same name in more than one schema. * Never: the unqualified object names are always used. Table/View: Always: ![Objects always qualified with tables](https://resources.jetbrains.com/help/img/idea/2026.2/qualify_objects_with_tables_always.png) Table/View: Never: ![Objects never qualified with tables](https://resources.jetbrains.com/help/img/idea/2026.2/qualify_objects_with_tables_never.png) | | Qualify objects in | Select when to qualify the objects in the given cases. * Always: the qualified object names are always used, for example `.`. * On collisions: the qualified object name is used only if the short name is ambiguous, for example, when there is the object with the same name in more than one schema. * Never: the unqualified object names are always used. JOIN completion: Always: ![Objects in JOIN completions always qualified](https://resources.jetbrains.com/help/img/idea/2026.2/qualify_objects_in_join_completions_always.png) JOIN completion: Never: ![Objects in JOIN completions never qualified](https://resources.jetbrains.com/help/img/idea/2026.2/qualify_objects_in_join_completions_never.png) | | Use aliases in completion for JOIN | Creates aliases for tables in the `JOIN` statement. ![Use aliases in completion for JOIN](https://resources.jetbrains.com/help/img/idea/2026.2/db_use_aliases_in_completion_for_join.png) | | Invert order of operands in auto-generated ON clause | Switches operands in the `ON` clause. When the checkbox is cleared, the `FROM` table comes the first in the `JOIN` condition. ![Invert order of operands in auto-generated ON clause](https://resources.jetbrains.com/help/img/idea/2026.2/db_invert_order_of_operands_in_on_clause.png) | | Suggest non-strict foreign keys based on the name matching | Generates you a list of possible code completion suggestions for `JOIN` statements. The code completion list includes suggestions of the columns from other tables that have the same names as columns from the table in the `JOIN` statement. Read more about debugging rules for this option in [Debug rules for virtual foreign keys](virtual-foreign-keys.html#debug-rules-for-virtual-foreign-keys). Checkbox selected: ![Suggest Non Strict Foreign Keys Based On The Name Matching is On](https://resources.jetbrains.com/help/img/idea/2026.2/db_suggest_non_strict_foreign_keys_based_on_the_name_matching_on.png) Checkbox cleared: ![Suggest Non Strict Foreign Keys Based On The Name Matching is Off](https://resources.jetbrains.com/help/img/idea/2026.2/db_suggest_non_strict_foreign_keys_based_on_the_name_matching_off.png) | | Automatically add aliases when completing table names | Creates an alias for a table name. ![Automatically add aliases when completing table names](https://resources.jetbrains.com/help/img/idea/2026.2/db_add_aliases_for_table_names.png) | | Suggest alias names in completion after table names | Suggests an alias for a table name when you use code completion (`Ctrl+Space` (Windows), `⌃ Space` (macOS), `⌃ Space` (IntelliJ IDEA Classic (macOS)), `⌃ Space` (macOS System Shortcuts), `Ctrl+Space` (XWin), `Ctrl+Space` (GNOME), `Ctrl+Space` (KDE), `Alt+/` (Emacs), `Ctrl+Space` (Sublime Text), `⌃ Space` (Sublime Text (macOS)), `⌃ Space` (Xcode), `Ctrl+Space` (Visual Studio), `⌃ Space` (Visual Studio (macOS)), `Ctrl+Space` (ReSharper), `⌃ Space` (ReSharper (macOS)), `Ctrl+Space` (QtCreator), `⌃ Space` (QtCreator (macOS)), `Ctrl+Space` (NetBeans), `Ctrl+Space` (Eclipse), `⌃ Space` (Eclipse (macOS))). ![Suggest alias names in completion after table names](https://resources.jetbrains.com/help/img/idea/2026.2/db_suggest_alias_names_in_completion.png) | | Custom aliases (table) | You can add a table name and the alias that you want to use for this table. To add the table-alias pair, click the Add alias button (![the Add alias button](https://resources.jetbrains.com/help/img/idea/2026.2/app.expui.general.add.svg)). | ## Completion tips and tricks Procedure: Autocomplete HTTP constants by typing the code number * After you specify an imported package name, such as `http`, you can type `404` to autocomplete the value to `http.StatusNotFound`. Procedure: Narrow down the suggestion list * Narrow down the suggestion list by typing any part of a word (even characters from somewhere in the middle) or invoking code completion after a dot separator . CLion displays suggestions containing the characters you've entered, regardless of their position. This makes the use of wildcards unnecessary. ![Code completion wild cards](https://resources.jetbrains.com/help/img/idea/2026.2/cl_completion_narrow_midword.png) In case of CamelCase or snake_case names, type the initial letters only. CLion automatically recognizes and matches the initial letters. Procedure: View reference * You can use the by pressing `Ctrl+Shift+I` (Windows), `⌥ Space` (macOS), `⌘ ⇧ I` (IntelliJ IDEA Classic (macOS)), `⌘ Y` (macOS System Shortcuts), `Ctrl+Shift+I` (XWin), `Ctrl+Shift+I` (GNOME), `Ctrl+Shift+I` (KDE), `Ctrl+Shift+I` (Emacs), `Ctrl+Shift+I` (Sublime Text), `⌥ Space` (Sublime Text (macOS)), `⌃ F1` (Xcode), `Alt+F12` (Visual Studio), `⌥ Space` (Visual Studio (macOS)), `Ctrl+Shift+I` (ReSharper), `⌥ Space` (ReSharper (macOS)), `Ctrl+Shift+I` (QtCreator), `Ctrl+Shift+I` (QtCreator (macOS)), `Ctrl+Shift+I` (NetBeans), `Ctrl+Shift+I` (Eclipse), `⌥ Space` (Eclipse (macOS)) when you select an entry in the suggestion list: ![Quick Definition for an item in the suggestion list](https://resources.jetbrains.com/help/img/idea/2026.2/cl_suggestion_list_defs.png) * You can use the [Quick Documentation view](viewing-inline-documentation.html) by pressing `Ctrl+Q` (Windows), `F1` (macOS), `⌃ J` (IntelliJ IDEA Classic (macOS)), `⌘ I` (macOS System Shortcuts), `Ctrl+Q` (XWin), `Ctrl+Q` (GNOME), `Ctrl+Q` (KDE), `Ctrl+Q` (Emacs), `Ctrl+Q` (Sublime Text), `Ctrl+Q` (Sublime Text (macOS)), `⌘ ⌃ ⇧ /` (Xcode), `Ctrl+K, I` (Visual Studio), `⌘ K, I` (Visual Studio (macOS)), `Ctrl+Q` (ReSharper), `⌃ Q` (ReSharper (macOS)), `Ctrl+Q` (QtCreator), `Ctrl+Q` (QtCreator (macOS)), `Ctrl+Q` (NetBeans), `Alt+Middle-Click` (Eclipse), `⌥ Middle-Click` (Eclipse (macOS)) or [automatically](#docpopup) when you select an entry in the suggestion list: ![Quick documentation for an item in the suggestion list](https://resources.jetbrains.com/help/img/idea/2026.2/cl_suggestion_list_docs.png) Procedure: View code hierarchy You can view [code hierarchies](analyzing-applications.html) when you've selected an entry from the suggestion list: * `Ctrl+H` (Windows), `⌃ H` (macOS), `⌃ H` (IntelliJ IDEA Classic (macOS)), `⌃ ⌥ H` (macOS System Shortcuts), `Ctrl+H` (XWin), `Ctrl+H` (GNOME), `Ctrl+H` (KDE), `Ctrl+H` (Emacs), `Ctrl+H` (Sublime Text), `Ctrl+H` (Sublime Text (macOS)), `⌃ H` (Xcode), `Ctrl+E, H` (Visual Studio), `⌘ E, H` (Visual Studio (macOS)), `Ctrl+Alt+H` (ReSharper), `⌘ ⌥ H` (ReSharper (macOS)), `Ctrl+Shift+T` (QtCreator), `⌃ ⇧ T` (QtCreator (macOS)), `Alt+Shift+F12` (NetBeans), `F4` (Eclipse), `F4` (Eclipse (macOS)): view type hierarchy * `Ctrl+Alt+H` (Windows), `⌃ ⌥ H` (macOS), `⌃ ⌥ H` (IntelliJ IDEA Classic (macOS)), `⌃ ⇧ H` (macOS System Shortcuts), `Ctrl+Alt+H` (XWin), `Ctrl+Alt+H` (GNOME), `Ctrl+Alt+H` (KDE), `Ctrl+Alt+H` (Emacs), `Ctrl+Alt+H` (Sublime Text), `⌃ ⌥ H` (Sublime Text (macOS)), `⌃ ⌥ H` (Xcode), `Ctrl+Alt+H` (Visual Studio), `⌃ ⌥ H` (Visual Studio (macOS)), `Ctrl+Alt+H` (ReSharper), `Ctrl+Alt+H` (ReSharper (macOS)), `Ctrl+Alt+H` (QtCreator), `⌃ ⌥ H` (QtCreator (macOS)), `Ctrl+Alt+H` (NetBeans), `Ctrl+Alt+H` (Eclipse), `⌃ ⌥ H` (Eclipse (macOS)): view call hierarchy. ## Troubleshooting If code completion does not work, this may be due to one of the following reasons: * The Power Save Mode is on (`File | Power Save Mode`). Turning it on minimizes power consumption of your laptop by eliminating the background operations, including error highlighting, on-the-fly inspections, and code completion. * Your file does not reside in a content root , so it does not get the required class definitions and resources needed for code completion. * A file with the symbols that you want to appear in completion is [excluded from project analysis](controlling-source-library-and-exclude-directories.html). * Code completion popup might not appear automatically if it takes too long to gather the completion options. For example, if the computer is busy with another task. In this case, you may still activate the completion popup manually via `Ctrl+Space` (Windows), `⌃ Space` (macOS), `⌃ Space` (IntelliJ IDEA Classic (macOS)), `⌃ Space` (macOS System Shortcuts), `Ctrl+Space` (XWin), `Ctrl+Space` (GNOME), `Ctrl+Space` (KDE), `Alt+/` (Emacs), `Ctrl+Space` (Sublime Text), `⌃ Space` (Sublime Text (macOS)), `⌃ Space` (Xcode), `Ctrl+Space` (Visual Studio), `⌃ Space` (Visual Studio (macOS)), `Ctrl+Space` (ReSharper), `⌃ Space` (ReSharper (macOS)), `Ctrl+Space` (QtCreator), `⌃ Space` (QtCreator (macOS)), `Ctrl+Space` (NetBeans), `Ctrl+Space` (Eclipse), `⌃ Space` (Eclipse (macOS)). ## See also ### Getting Started [Editor basics](using-code-editor.html)