How to get or read a single data in SQLite database?

[jchd]

Only the ISO timestamp format can sort natively. mm/dd/yyyy and other variations are for human consumption only; forget it in storage!

You can still display the format of your choice in the resultset of a query: use string functions for that.

Also, if you want local time, don't use a literal fixed value, use the 'localtime' modifier in the date functions. That way summer/winter times are correct. I recommend storing UTC times and display local times when needed. If you store local times, you never know if that was east- or west-coast time or anything in between (if you live in the US for instance).

[Andreik]

In this case you should save date and time in database as a single column as datetime type. If you need certain portions of this data then use SQLite Date and Time functions.

[jchd]

Looking again at your last post, I'd urge you to normalize your database. Category should be a separate table and you should use it as a foreign key in your main table.

[HezzelQuartz]

On 9/4/2024 at 4:53 PM, jchd said:

Looking again at your last post, I'd urge you to normalize your database. Category should be a separate table and you should use it as a foreign key in your main table.

could you explain about separate table and use it as foreign key?

I also have another question
If several column value in a row has been inserted, how can I insert the rest that is still null?
I mean how to insert / update only description part in the picture below?

Oh yes, Is there any udf or function to use mysql or another sql?
Could you please tell me?

Thank You
 

[Andreik]

Here is an example about what @jchd told you about having a foreign key on Category and an update example.

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#include <SQLite.au3>
#include <Array.au3>

_SQLite_Startup()
$hDB = _SQLite_Open()

; Create categories and products tables
_SQLite_Exec($hDB, 'CREATE TABLE categories(' & _
                                'idCategory INTEGER PRIMARY KEY,' & _
                                'Category VARCHAR(32) NOT NULL' & _
                            ');' _
            )

_SQLite_Exec($hDB, 'CREATE TABLE products' & _
                            '(idProduct INTEGER PRIMARY KEY,' & _
                            'idCategory INTEGER NOT NULL,' & _
                            'ProductName VARCHAR(64) NOT NULL,' & _
                            'Price DECIMAL(10, 5) NOT NULL,' & _
                            'RegisterDate DATETIME NOT NULL,' & _
                            'Description TEXT,' & _
                            'FOREIGN KEY(idCategory) REFERENCES categories(idCategory)' & _
                        ');' _
            )

; Insert categories
_SQLite_Exec($hDB, 'INSERT INTO categories(Category) VALUES("Book"), ("Pen"), ("Eraser");')

; Insert some products
_SQLite_Exec($hDB, 'INSERT INTO products(idCategory, ProductName, Price, RegisterDate) VALUES' & _
                   '(1, "Book A", 55000, "2024/09/05 10:10:10"),' & _
                   '(1, "Book B", 35000, "2024/09/01 15:10:10"),' & _
                   '(1, "Book C", 75000, "2024/09/02 11:10:10"),' & _
                   '(1, "Book D", 15000, "2024/09/04 10:10:10"),' & _
                   '(2, "Pen A", 15000, "2024/09/03 15:10:10"),' & _
                   '(2, "Pen B", 25000, "2024/09/03 13:10:10"),' & _
                   '(2, "Pen C", 35000, "2024/09/04 08:10:10"),' & _
                   '(2, "Pen D", 20000, "2024/09/04 09:10:10"),' & _
                   '(3, "Eraser A", 25000, "2024/08/04 23:10:10"),' & _
                   '(3, "Eraser B", 25000, "2024/10/04 13:10:10"),' & _
                   '(3, "Eraser C", 25000, "2022/08/04 15:10:10"),' & _
                   '(3, "Eraser D", 25000, "2025/03/04 23:50:10")' _
            )

Local $aResult, $iRows, $iColumns

; Read all products from table
_SQLite_GetTable2d($hDB, 'SELECT p.idProduct, c.Category, p.ProductName, p.Price, p.RegisterDate, p.Description ' & _
                         'FROM products p INNER JOIN categories c ON p.idCategory=c.idCategory;', $aResult, $iRows, $iColumns)
_ArrayDisplay($aResult)

; Read all products from table ordered by date descending
_SQLite_GetTable2d($hDB, 'SELECT p.idProduct, c.Category, p.ProductName, p.Price, p.RegisterDate, p.Description ' & _
                         'FROM products p INNER JOIN categories c ON p.idCategory=c.idCategory ' & _
                         'ORDER BY RegisterDate DESC;', $aResult, $iRows, $iColumns)
_ArrayDisplay($aResult)

; Update description of the first product
_SQLite_Exec($hDB, 'UPDATE products SET Description = "Whatever you want" WHERE idProduct = 1;')
_SQLite_GetTable2d($hDB, 'SELECT p.idProduct, c.Category, p.ProductName, p.Price, p.RegisterDate, p.Description ' & _
                         'FROM products p INNER JOIN categories c ON p.idCategory=c.idCategory;', $aResult, $iRows, $iColumns)
_ArrayDisplay($aResult)

_SQLite_Close($hDB)
_SQLite_Shutdown()

 

Edited September 5 by Andreik

[HezzelQuartz]

@Andreik@jchd
How can I insert description into my table below?

I can use this code below to do that:

update Book set Description = 'This book has newer release' where Product = 'Book A'

But, can I use another command, something like:

insert Into Book (Description) Values ('This book has newer release') where Product = 'Book A'?

Or another command maybe?

Thank You

 

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Oh yes, Is there any udf or function to use mysql or another sql?
Could you please tell me?

Thank You

[bogQ]

you can not do "insert where", "update where something=something AND somethingelse=somethingelse" will do the update, insert do not have that because your inserting and as SQLite does not guarantees order it does not matter where its inserted and, so "insert where" is impossible. + that will be illogical 

 

But you can allwayes remove before reinserting something if that is what you wish

DELETE FROM x WHERE id = 1;

INSERT INTO x VALUES (1, 'something', 'something', ...);

Edited September 9 by bogQ

[jchd]

You can also use UPSERT, which means update if exists else insert. Use with caution !

All of this is common to almost every SQL engine I know of (Postgres, Mysql, sql server, oracle, ...). SQLite is by far the simplest to install and use.

Invest time to study SQL (w3school for instance) and SQLite documentation.

[HezzelQuartz]

@Andreik@bogQ@jchd

I have a few more question

How to delete last rowid without knowing last rowid number?
I tried using this one and it worked

delete from Book where rowid = (SELECT max(rowid) FROM Book)

Is there easier way or another good alternatif?

----------------------------------------------------------------------------------------------------------------------------------------------------

How to use _SQLite_Display2DResult_SQLite?

After doing

$iRval = _SQLite_GetTable2D($hDatabase, 'SELECT * FROM Book', $aResult, $iRows, $iColumns)

I can continue with this below, the table is appeared
 

_ArrayDisplay($aResult)

But, I can't continue with this below, nothing happened, no table appeared

_SQLite_Display2DResult($aResult)

Thank You

Edited September 13 by HezzelQuartz

[bogQ]

Engine not having last row identifier only thing you can do is something similar to that what you already done 

Additional ways:

"WHERE rowid = (SELECT rowid FROM your_table ORDER BY rowid ESC LIMIT 1);" or "WHERE rowid IN (... );"

But i do think your way is the fastest and most easy to read

 

_SQLite_Display2DResult Returns or prints to Console a formated display of a 2Dimensional array

Display result to console (scite console for example) if $bReturn is properly set, so it will not popup window, if changed from default it will return data to your variable

Not tested it at the moment but to manage data you probably need to do something like this

$data = _SQLite_Display2DResult($aResult, 0, true)

 

Edited September 13 by bogQ

[HezzelQuartz]

@bogQ@Andreik@jchd and everyone
I have another question

How to select last 5 rowid?

I tried using this one and I Think it worked
 

SELECT * FROM ProductInformation where rowid between (SELECT max(rowid)-5 FROM ProductInformation) And (SELECT max(rowid) FROM ProductInformation)

Did I do anything wrong?
Is there easier way or another good alternatif so that the command can be more simple and easier to read?

Thank You

[jchd]

Use this, provided "no" is an alias for "rowid" (that is if "no" is INTEGER PRIMARY KEY):

SELECT * FROM ProductInformation order by no desc limit 5;

If you insist on showing this resultset in ascending "no" order, use that:

select * from (SELECT * FROM ProductInformation order by no desc limit 5) order by no;

[HezzelQuartz]

@Andreik@jchd@bogQ and everyone

Sorry, I want to ask again

From My table below, How to count how many "Pen" Appear in Category?

I tried using this command, and it worked

SELECT category, count(*) FROM Book where category = 'Pen'

1. Is there easier way or another good alternatif so that the command can be more simple and easier to read?

2. Could you please explain what (*) means?

3. What function in autoit should I use to insert that sqlite command above? _SQLite_QuerySingleRow?
 

[jchd]

1) The SQL you use is the same number of words in your question. The SQL seems quite readable to me.

2) What if you read the SQLite documentation? https://www.sqlite.org/index.html

3) Yes. You ask for one row, so get one row.

[HezzelQuartz]

@jchd@bogQ@Andreik and everyone

Sorry, I want to ask again

From My table below, how to get only 'product' column with 'Pen' Category into arrays?

I tried using this command, and it worked
 

_SQLite_GetTable2D($hDatabase, "SELECT Product from Book where Category = 'Pen'", $aResult, $iRows, $iColumns)

MsgBox(0, "Price of Book B", $aResult[1][0])
MsgBox(0, "Price of Book B", $aResult[2][0])
MsgBox(0, "Price of Book B", $aResult[3][0])
MsgBox(0, "Price of Book B", $aResult[4][0])

1. Is there easier way or another good alternatif so that the command can be more simple and easier to read?

2. Actually I prefer to use any function similar to _SQLite_QuerySingleRow, Can I use another function? maybe _SQLite_Query?

3. If _SQLite_Query can be used, I am confused. How to use that function? Could you all please give any idea, clue, or else?

Edited October 1 by HezzelQuartz

[jchd]

For resultset with only one column and more than one row, use _SQLite_GetTable()

For resultset with more columns and more than one row, use _SQLite_GetTable2D()

Forget _SQLite_Query and friends.

[HezzelQuartz]

On 10/1/2024 at 3:48 PM, jchd said:

For resultset with only one column and more than one row, use _SQLite_GetTable()

For resultset with more columns and more than one row, use _SQLite_GetTable2D()

Forget _SQLite_Query and friends.

@jchd and anyone

How can I get how many rows are available in one column using either _SQLite_GetTable() or _SQLite_GetTable2D()?

Actually I can get total row using different command:
 

SELECT Product, count(*) FROM Book

But I really prefer to get row number using _SQLite_GetTable() or _SQLite_GetTable2D()?

[jchd]

Read the documentation about these two functions.