SQL | Temporary tables and table variables exercise | Temporary tables - first letter count of events

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Software ==> SQL  (198 exercises)
Version ==> Any version of SQL Server
Topic ==> Temporary tables and table variables  (9 exercises)
Level ==> Relatively easy
Course ==> Advanced SQL
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Using the INTO syntax, create a temporary table holding a count of the number of event names beginning with the same letter.

Something

Use LEFT to return only the first letter from the EventName column, then GROUP BY this and perform a COUNT.

The problem with INTO is that it decides the data type of the column based on the current data. Try adding XZ as a first letter with a count of 57 using INSERT INTO:

-- Trying to add this data gives an error

INSERT INTO #EventsByLetter

values ('xz', 57)

This should generate an error: 

Data type clash problem caused by INTO creation

The original data type is too small. 

 

Add a statement at the top of your query to create a new table called #EventsByLetter with two columns:

Column Type
First letter varchar(2)
Number of events int

Now change your SELECT statement so that it adds the first letter summary rows into this table, rather than creating a new table.  The syntax of the command to insert rows into an existing table looks something like this:

INSERT INTO TableName (

Column1,

...,

ColumnN

)

SELECT (

Value1,

...,

ValueN

)

FROM ...

When you run this revised query, it should accommodate the xz insertion also, and allow you to display the final results:

CREATE temp table then INSERT values

Use ORDER BY to put the results into alphabetical order by the First Letter column.

 

Optionally save this as Tables of Temp-tation.sql, then close it down.

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