![]() I'm sure there are probably other things I am overlooking. Fourth, opening the cursor twice seems like it would execute the query twice, though given the placement and context, it's probably got it cached somewhere (hopefully). Third, building the array in the first place using array_append seems extremely inefficient. Second, the set of records returned from unnesting would not be indexed for the join which means a sequential scan. ![]() First, I'm not sure of the penalty for unnesting an array into a SET OF object. SELECT * FROM table1 INNER JOIN (SELECT * FROM unnest(result_array)) AS table2 ON ( blah blah ) WHERE blah Then, when I need to use the results in a query, I do something like: Some code that pushes the current temp record onto the end of an array However, there are some cases in the stored procedure where some of the result sets returned by these cursors are also needed as inputs to additional queries. The procedure currently uses cursors to return multiple result sets to the program executing the procedure. However, without getting into too many details, I have another performance-related question. Then, run the INSERT INTO query to insert the records into the table: INSERT INTO #products_temp_table (product_id, product_name, price)ģ records will be inserted into the table.I have previously discussed my very long PL/PGSQL stored procedure on this list. Optionally, you can use the CREATE TABLE approach in order to create the global temporary table: CREATE TABLE #products_temp_table ( You’ll get the same 3 records where the price is greater than 300: product_id You can then run the following SELECT query: SELECT * FROM #products_temp_table Here is the query to create the global temporary table using the SELECT INTO approach: SELECT product_id, product_name, priceģ records will be affected: (3 rows affected) The global temporary table will be available across different connections. You can also create a global temporary table by placing double hash (#) before the temporary table name. To drop the table use: DROP TABLE #products_temp_tableĬreate a Global Temporary Table in SQL Server Rerun the SELECT query in order to check the content of the table: SELECT * FROM #products_temp_tableĪs you can see, there are 3 records where the price is greater than 300: product_id You’ll notice that 3 records were affected: (3 rows affected) Once you created the temporary table, you’ll need to insert the records into the table using the INSERT INTO query: INSERT INTO #products_temp_table (product_id, product_name, price) Let’s recreate the temporary table using the second CREATE TABLE approach: CREATE TABLE #products_temp_table ( (2) Create a Temporary Table in SQL Server Using the CREATE TABLE Approach Invalid object name '#products_temp_table'. Notice that the table no longer exists: Msg 208, Level 16, State 0, Line 1 You can drop the temporary table using the DROP TABLE query: DROP TABLE #products_temp_tableĪfter dropping the table, try to run the SELECT query again: SELECT * FROM #products_temp_table You can check the content of the temporary table by running the following SELECT query: SELECT * FROM #products_temp_tableĪs you can see, there are currently 3 rows in the table where the price is greater than 300: product_id You can then create a temporary table (called #products_temp_table) using the SELECT INTO Approach: SELECT product_id, product_name, priceĪfter running the query, you’ll notice that 3 rows were affected: (3 rows affected) The ultimate goal is to create a temporary table (from the ‘products’ table) for all the records where the price is greater than 300. The current ‘products’ table contains the following columns and data: product_id In the example below, you’ll see how to create a temporary table from an existing table called products. (1) Create a Temporary Table in SQL Server Using the SELECT INTO Approach You’ll also learn how to create a global temporary table. In the next section, you’ll see how to create a temporary table in SQL Server using the two approaches described above. ![]() You can drop a temporary table using the DROP TABLE query (or simply by closing the connection that was used to create the temporary table): DROP TABLE #name_of_temp_table Under both approaches, you must include the hash symbol (#) before the temporary table name. Note that once you created the table under the second approach, you’ll need to insert the records into the table using an INSERT INTO query: INSERT INTO #name_of_temp_table (column_1, column_2, column_3.) (2) The CREATE TABLE approach: CREATE TABLE #name_of_temp_table ( (1) The SELECT INTO approach: SELECT column_1, column_2, column_3. Here are two approaches to create a temporary table in SQL Server:
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