#SQLITE INSERT VALUE NUL UPDATE#
#SQLITE INSERT VALUE NUL FULL#
#SQLITE INSERT VALUE NUL CODE#
#SQLITE INSERT VALUE NUL WINDOWS#

SQLite's NULL return is arguably correct, since all three inputs are not NULL (nor, as another responder mentioned, NaN-degenerated-to-NULL), but a meaningful total cannot be computed. The sum() and total() aggregate functions return the sum of all non-NULL values in the group. Now, if I remember correctly, Inf + (-Inf) is undefined under IEEE 754, and since the document you linked to also states: A binary64 can also be 0.0 (and -0.0), positive and negative infinity and 'NaN' or 'Not-a-Number'. 0 So I have a Table in some sqlite3 DB that has the following structure: CREATE TABLE table00 ( id INTEGER PRIMARY KEY AUTOINCREMENT, value VARCHAR (100) UNIQUE NOT NULL ) I need to retrieve the id from this table to use it in some other query. This gives a range of positive values between approximately 1.7976931348623157e+308 and 4.9406564584124654e-324 with an equivalent range of negative values. So-called 'REAL' or floating point values are stored in the IEEE 754 Binary-64 format. You can try it if main example won't work.That's because you overflowed the Binary-64 range representation: Some sources tells that it's not enough and you should do something like this: with FDQuery1.ParamByName('name') do beginīut I can't confirm it.

#SQLITE INSERT VALUE NUL CODE#

It's not very good idea to execute query as String without parameters because this code is vulnerable to SQL injections. To do so, one should change the value of the NULLALWAYSDISTINCT define in the sqliteInt.h source file and recompile. Something like this: //Assign FDConnection1 to FDQuery1's Connection propertyį := 'INSERT OR REPLACE INTO Clients(Name,Notes) VALUES (:nameval,:notesval)' It is possible to make SQLite treat NULLs as distinct for the purposes of the SELECT DISTINCT and UNION. So, you have to use FDQuery to insert Null values, I suppose. Then call the Clear method: with FDQuery1.ParamByName('name') do begin To set the parameter value to Null, specify the parameter data type,

#SQLITE INSERT VALUE NUL UPDATE#

Id := FDConnection1.ExecSQLScalar('SELECT FROM Clients VALUES id WHERE Name=:nameval',) įDConnection1.ExecSQL('UPDATE Clients SET Notes=:noteval WHERE id=:idval)',) Īccording to Embarcadero documentation ( here ): Empty struct that can be used to fill in a query parameter as NULL. This SQLite IS NOT NULL example will insert records into the temp table where the lastname does not contain a null value. Once we add NOT NULL Constraint on a required column and if we try to insert or update a NULL value in a new or existing row then it will throw an error. Like this: FDConnection1.ExecSQL('INSERT OR REPLACE INTO Clients(Name) VALUES (:nameval)',) IfThen(someNote.isEmpty,'NULL','''+Sanitize(someNote)+''')+') ') Įdit2: Currently I see an option of creating new row with 'INSERT OR REPLACE' and then use multiple UPDATEs in a row for each non-empty value. I've tried to overload it and specify and it didn't help.Ĭurrently I have to do it like this and I hate this messy code: FDConnection1.ExecSQL('INSERT OR REPLACE INTO Clients(Name,Notes) VALUES ('+ I am seeing different errors for a foreign key conflict (no record exists) for an INSERT versus an INSERT. 3 Answers Sorted by: 37 Use a tuple, I.E.: db.

#SQLITE INSERT VALUE NUL WINDOWS#

This raises an exception: could not convert variant of type (Null) into type (OleStr) (1) By rt12 (rt121212121) on 21:20:19 source I use the Python sqlite3 bindings for sqlite, and on Windows I have 3.35.5 and on Linux I have 3.38.0. This is how I tried it: var someName,someNote: string įDConnection1.ExecSQL('INSERT OR REPLACE INTO Clients(Name,Notes) VALUES (:nameval,:notesval)', Creating multiple variants of ExecSQL and nesting If statements isn't an option too - there are too many optional fields (18, to be exact). If value is empty, I would like to keep it at Null or default value. In my application values are provided by user input and functions, any many of them are optional. I use Delphi 10, FireDAC and local SQLite DB.Įdit: Provided code is just an example. When you create a new table using the CREATE TABLE statement, you can specify default values for columns, or a NULL if a default value is not specified.

#SQLITE INSERT VALUE NUL FULL#

I don't see why would I want to have a DB full of empty strings in fields.

Sqlite insert value nul