The Query toolΒΆ

The Query tool is a powerful, feature-rich environment that allows you to execute arbitrary SQL commands and review the result set. If you access the Query tool via the Query Tool menu option on the Tools menu, you can:

  • Issue ad-hoc SQL queries.
  • Execute arbitrary SQL commands.
  • Save the data displayed in the output panel to a CSV file.
  • Review the execution plan of a SQL statement in either a text or a graphical format.
  • View analytical information about a SQL statement.

If you open the Query tool via the View Data context-menu, the Query tool acts as a data editor, allowing you to:

  • View or modify the data that is stored in a table.
  • Filter the result set.
  • Save the data displayed in the output panel to a CSV file.
  • Review the execution plan of a SQL statement in either a text or a graphical format.
  • View analytical information about a SQL statement.
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The Query tool features a toolbar that allows quick access to frequently used options, and a work environment divided into two panels:

  • The upper panel of the Query tool contains the SQL Editor. You can use the panel to manually enter a query, or review the query that generated the result set displayed in the lower panel.
  • The lower panel of the Query tool contains the Data Output panel. The output panel displays the result of a query, or information about a query’s execution plan.

pgAdmin allows you to open multiple copies of the Query tool (in individual tabs) simultaneously. For example, if you select Query tool from the Tools menu, the Query tool opens in a tab labeled Query-1; if you open the Query tool again (without closing Query-1), a second copy will open in Query-2. To close a copy of the Query tool, click the X in the upper-right hand corner of the tab bar.

The Query tool Toolbar

The Query tool toolbar uses context-sensitive icons that provide shortcuts to frequently performed tasks. If an icon is highlighted, the option is enabled; if the icon is grayed-out, the task is disabled.

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Hover over an icon to display a tooltip that describes the icon’s functionality:

Icon Behavior
Open File Click the Open File icon to display a previously saved query in the SQL Editor.
Save Click the Save icon to save the query that is currently displayed in the SQL Editor.
Copy Click the Copy icon to copy the currently selected row.
Paste Click the Paste icon to paste the content that is currently on the clipboard.
Add New Row Use the Add New Row icon to add a new row in the output panel.
Filter

Click the Filter icon to open a dialog that allows you to write and apply a filter for the content currently displayed in the output panel. Click the down arrow to open the Filter drop- down menu and select from pre-defined options:

Select Remove to remove the currently applied filter and display the complete result set.

Select By selection to refresh the displayed data, displaying only those rows that have columns that match the currently highlighted value.

Select Exclude selection to refresh the displayed data, excluding those rows that have columns that match the currently highlighted value.

No limit Use the No limit drop-down listbox to specify how many rows to display in the output panel. Select from: No limit (the default), 1000 rows, 500 rows, or 100 rows.
Execute/Refresh

Click the Execute/Refresh icon to either execute or refresh the query highlighted in the SQL editor panel. Click the down arrow to access other execution options:

Select Execute/Refresh to invoke the SQL command and refresh the result set.

Select Explain to view an explanation plan for the current query. The result of the EXPLAIN is displayed graphically on the Explain tab of the output panel, and in text form on the Data Output tab.

Select Explain analyze to invoke an EXPLAIN ANALYZE command on the current query.

Navigate through the Explain Options menu to select options for the EXPLAIN command:

Select Verbose to display additional information regarding the query plan.

Select Costs to include information on the estimated startup and total cost of each plan node, as well as the estimated number of rows and the estimated width of each row.

Select Buffers to include information on buffer usage.

Select Timing to include information about the startup time and the amount of time spent in each node of the query.

Add a check next to Auto-Rollback to instruct the server to automatically roll back a transaction if an error occurs during the transaction.

Add a check next to Auto-Commit to instruct the server to automatically commit each transaction. Any changes made by the transaction will be visible to others, and durable in the event of a crash.

Stop Click the Stop icon to cancel the execution of the currently running query.
Clear query window Use options on the Clear query window drop-down menu to erase the contents of the SQL editor panel or the History tab.
Download as CSV Click the Download as CSV icon to download the result set of the current query to a comma-separated list.

The SQL Editor Panel

The SQL editor panel contains a workspace for entering commands; you can read a query from a file, or type a query. The SQL editor features syntax coloring and autocompletion to help you develop queries.

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To use autocomplete, begin typing your query; when you would like the Query editor to suggest object names or commands that might be next in your query, press the Control+Space key combination. For example, type “*SELECT * FROM* ” (without quotes, but with a trailing space), and then press the Control+Space key combination to select from a popup menu of autocomplete options.

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After entering a query, select the Execute/Refresh icon from the toolbar. The complete contents of the SQL editor panel will be sent to the database server for execution. To execute only a section of the code that is displayed in the SQL editor, highlight the text that you want the server to execute, and click the Execute/Refresh icon:

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The message returned by the server when a command executes is displayed on the Messages tab of the output panel. If the command is successful, the Messages tab displays execution details:

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The editor also offers several features that help with code formatting:

  • The auto-indent feature will automatically indent text to the same depth as the previous line when you press the Return key.
  • Block indent text by selecting two or more lines and pressing the Tab key.
  • Block outdent text that has been indented using the Shift+Tab key combination.
  • Comment out SQL by selecting some text and pressing Control+K.
  • Uncomment SQL by selecting some text starting with a comment and pressing Control+Shift+K.
  • Shift the selected text to upper case by pressing Control+U.
  • Shift the selected text to lower case by pressing Control+Shift+U.

The Data Output Panel

Use the Data Output panel of the Query tool to view data and information generated by a query in the SQL editor, or to View Data for an object currently selected in the pgAdmin tree control.

The Data Output panel organizes output through the following tabs: Data Output, Explain, Messages, and History.

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If the Query tool is opened through the Query tool menu option on the Tools menu, you can use the Data Output tab to view the results of an arbitrary query in a table format. If the Query tool is opened through a View Data context menu, the Data Output tab will display the data stored in the table from which the Query tool was opened.

  • Click a column header to sort data by that column. Click again to reverse the sorting order.
  • If enabled, use the Filter options from the Query tool toolbar to refine the result set displayed on the Data Output tab.
  • If enabled, use the No limit drop-down to specify how many rows to display on the Data Output tab.
  • If enabled, use the Execute/Refresh options to retrieve query execution information and set query execution options.
  • Use the Download as CSV icon to download the content of the Data Output tab as a comma-delimited file.

All rowsets from previous queries or commands that are displayed in the Data Output panel will be discarded when you invoke another query; open another query tool browser tab to keep your previous results available.

Use the Explain tab to view a graphical representation of a query:

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To generate a graphical explain diagram, open the Explain tab, and select Explain, Explain Analyze, or one or more options from the Explain options menu on the Execute/Refresh drop-down. Please note that EXPLAIN VERBOSE cannot be displayed graphically. Hover over an icon on the Explain tab to review information about that item; a popup window will display information about the selected object:

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Note that the query plan that accompanies the Explain analyze is available on the Data Output tab.

Use the Messages tab to view information about the last-executed query:

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If the server returns an error, the error message will be displayed on the Messages tab, and the syntax that cause the error will be underlined in the SQL editor.

If a query succeeds, the Messages tab displays how long the query took to complete and how many rows were retrieved:

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Use the History tab to review activity for the current session:

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The History tab displays:

  • The date and time that a query was invoked.
  • The text of the query.
  • The number of rows returned by the query.
  • The amount of time it took the server to process the query and return a result set.
  • Messages returned by the server (not noted on the Messages tab).

To erase the content of the History tab, select Clear history from the Clear query window drop-down menu.