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1. FLUTTER SQLITE TRANSACTION UPDATE
2. FLUTTER SQLITE TRANSACTION CODE
3. FLUTTER SQLITE TRANSACTION WINDOWS

Using a Transactionīy default, SQLite will evaluate every INSERT / UPDATE statement within a unique transaction. Yikes! 2 hours and 45 minutes! That's only 85 inserts per second.

FLUTTER SQLITE TRANSACTION CODE

This is going to be slow because the SQL will be compiled into VDBE code for every insert and every insert will happen in its own transaction. Sqlite3_exec(db, sSQL, NULL, NULL, &sErrMsg) We're going to generate the SQL string using the values read from the file and invoke that SQL operation using sqlite3_exec: sprintf(sSQL, "INSERT INTO TTC VALUES (NULL, '%s', '%s', '%s', '%s', '%s', '%s', '%s')", sRT, sBR, sVR, sST, sVI, sDT, sTM) Great! We can do 920,000 inserts per second, provided we don't actually do any inserts :-) Running the code as-is doesn't actually perform any database operations, but it will give us an idea of how fast the raw C file I/O and string processing operations are. Printf("Imported %d records in %4.2f seconds\n", n, (clock() - cStartClock) / (double)CLOCKS_PER_SEC) SVI = strtok (NULL, "\t") /* Get Vehicle */ SST = strtok (NULL, "\t") /* Get Stop Number */ SVR = strtok (NULL, "\t") /* Get Version */ SBR = strtok (NULL, "\t") /* Get Branch */ SRT = strtok (sInputBuf, "\t") /* Get Route */ * Open input file and import into Database*/ Sqlite3_exec(db, TABLE, NULL, NULL, &sErrMsg) * Open the Database and create the Schema */ #define TABLE "CREATE TABLE IF NOT EXISTS TTC (id INTEGER PRIMARY KEY, Route_ID TEXT, Branch_Code TEXT, Version INTEGER, Stop INTEGER, Vehicle_Index INTEGER, Day Integer, Time TEXT)" #define DATABASE "c:\\TTC_schedule_scheduleitem_10-27-2009.sqlite" #define INPUTDATA "C:\\TTC_schedule_scheduleitem_10-27-2009.txt" Input data is a 28 MB TAB-delimited text file of theĬomplete Toronto Transit System schedule/route info The Code: A simple C program that reads the text file line-by-line, splits the string into values and then inserts the data into an SQLite database. The SQLite version I happen to have is a bit older (3.6.7), but I suspect these results will be comparable to the latest release (please leave a comment if you think otherwise). I'm using the SQLite "Amalgamation", compiled directly into my test application.The code is compiled with Visual C++ 2005 as "Release" with "Full Optimization" (/Ox) and Favor Fast Code (/Ot).

FLUTTER SQLITE TRANSACTION WINDOWS

We're going to start with some simple data: "Use a transaction!"), I thought it best to write some C code and actually measure the impact of various options. The Experiment: Rather than simply talking about performance tips in the general sense (i.e.

It was not a trivial matter to figure out what all of the options and techniques were, so I thought it prudent to create this community wiki entry to share the results with Stack Overflow readers in order to save others the trouble of the same investigations. It turns-out that the performance of SQLite can vary significantly (both for bulk-inserts and selects) depending on how the database is configured and how you're using the API. Rationale: Initially I was disappointed with the performance I was seeing. SQLite is ideal for this situation because it's fast, it requires no specialized configuration, and the database is stored on disk as a single file. We have large amounts of configuration data stored in XML files that are parsed and loaded into an SQLite database for further processing when the application is initialized. Bulk-insert performance of a C application can vary from 85 inserts per second to over 96,000 inserts per second!īackground: We are using SQLite as part of a desktop application.