Need a good method to change SQLite column data type

Question

I have a table with an 'int' column. During a software update, I want to change it to a "long" data type. It seems that SQLite does not provide an option (in the alter statement) for modifying / modifying column properties. Since I want to perform an update, the table may contain data that the user should not lose. Therefore, please offer me a good way to change the data type property of a column without losing data.

One way suggested in the search links is to create a temporary table, copy the records from the existing table, delete the existing table, and rename the temporary table. I doubt it is effective.

Your help was appreciated!

Hi

Vivek Ragunathan

Answer 1

I used the following instructions to change the type of a column.

CREATE TABLE IF NOT EXISTS **TEMP_TABLE** (id integer primary key autoincrement, **col2change integer not null**, ...)

INSERT INTO TEMP_TABLE SELECT * FROM EXISTING_TABLE

DROP TABLE EXISTING_TABLE

ALTER TABLE TEMP_TABLE RENAME TO EXISTING_TABLE

I changed the int column in the existing table to an integer. For a few hundred lines, this was fast enough.

Answer 2

There are no data types in SQLite3 columns, only affinities - there is no use in changing the column type from int to long.

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Answer 3

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Answer 4

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Answer 5

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