exec


Description:

[ CCode ( cname = "_sqlite3_exec" ) ]
public int exec (string sql, Callback? callback = null, out string? errmsg = null)

Example: Create table:

public static int main (string[] args) {
Sqlite.Database db;
string errmsg;

// Open/Create a database:
int ec = Sqlite.Database.open ("test.db", out db);
if (ec != Sqlite.OK) {
stderr.printf ("Can't open database: %d: %s\n", db.errcode (), db.errmsg ());
return -1;
}


string query = """
CREATE TABLE User (
id INT PRIMARY KEY NOT NULL,
name TEXT NOT NULL
);
"""
;

// Execute our query:
ec = db.exec (query, null, out errmsg);
if (ec != Sqlite.OK) {
stderr.printf ("Error: %s\n", errmsg);
return -1;
}

print ("Created.\n");

return 0;
}

valac --pkg sqlite3 create-table.vala

Example: Insert:

public static int main (string[] args) {
Sqlite.Database db;
string errmsg;

// Open a database:
int ec = Sqlite.Database.open ("test.db", out db);
if (ec != Sqlite.OK) {
stderr.printf ("Can't open database: %d: %s\n", db.errcode (), db.errmsg ());
return -1;
}

// Required table:
// CREATE TABLE User (
// id INT PRIMARY KEY NOT NULL,
// name TEXT NOT NULL
// );


// Insert: (See Sqlite.Database.prepare)
string query = """
INSERT INTO User (id, name) VALUES (1, 'Hesse');
INSERT INTO User (id, name) VALUES (2, 'Frisch');
"""
;
ec = db.exec (query, null, out errmsg);
if (ec != Sqlite.OK) {
stderr.printf ("Error: %s\n", errmsg);
return -1;
}

int64 last_id = db.last_insert_rowid ();
print ("Last inserted id: %" + int64.FORMAT + "\n", last_id);

return 0;
}

valac --pkg sqlite3 insert.vala

Example: Select:

private static int exec_callback (int n_columns, string[] values, string[] column_names) {
for (int i = 0; i < n_columns; i++) {
print ("%s: %s\n", column_names[i], values[i]);
}
return 0;
}

public static int main (string[] args) {
Sqlite.Database db;
string errmsg;

// Open a database:
int ec = Sqlite.Database.open ("test.db", out db);
if (ec != Sqlite.OK) {
stderr.printf ("Can't open database: %d: %s\n", db.errcode (), db.errmsg ());
return -1;
}

// Required table:
// CREATE TABLE User (
// id INT PRIMARY KEY NOT NULL,
// name TEXT NOT NULL
// );

// Example data:
// INSERT INTO User (id, name) VALUES (1, 'Hesse');
// INSERT INTO User (id, name) VALUES (2, 'Frisch');

// Insert:
string query = "SELECT * FROM User";
ec = db.exec (query, exec_callback, out errmsg);
if (ec != Sqlite.OK) {
stderr.printf ("Error: %s\n", errmsg);
return -1;
}

// Outpu: (see exec_callback)
// ``id: 1``
// ``name: Hesse``
// ``id: 2``
// ``name: Frisch``

return 0;
}

valac --pkg sqlite3 select.vala

Example: Update:

public static int main (string[] args) {
Sqlite.Database db;
string errmsg;

// Open a database:
int ec = Sqlite.Database.open ("test.db", out db);
if (ec != Sqlite.OK) {
stderr.printf ("Can't open database: %d: %s\n", db.errcode (), db.errmsg ());
return -1;
}

// Required table:
// CREATE TABLE User (
// id INT PRIMARY KEY NOT NULL,
// name TEXT NOT NULL
// );

// Required data:
// INSERT INTO User (id, name) VALUES (1, 'Hesse');
// INSERT INTO User (id, name) VALUES (2, 'Frisch');


// Delete "Frisch" via id:
string query = "UPDATE User SET name = 'Hermann' WHERE id = 1;";
ec = db.exec (query, null, out errmsg);
if (ec != Sqlite.OK) {
stderr.printf ("Error: %s\n", errmsg);
return -1;
}

int changes = db.total_changes ();
print ("Affected rows: %d\n", changes);

return 0;
}

valac --pkg sqlite3 update.vala

Example: Delete:

public static int main (string[] args) {
Sqlite.Database db;
string errmsg;

// Open a database:
int ec = Sqlite.Database.open ("test.db", out db);
if (ec != Sqlite.OK) {
stderr.printf ("Can't open database: %d: %s\n", db.errcode (), db.errmsg ());
return -1;
}

// Required table:
// CREATE TABLE User (
// id INT PRIMARY KEY NOT NULL,
// name TEXT NOT NULL
// );

// Required data:
// INSERT INTO User (id, name) VALUES (1, 'Hesse');
// INSERT INTO User (id, name) VALUES (2, 'Frisch');


// Delete "Frisch" via id:
string query = "DELETE FROM User WHERE id = 2;";
ec = db.exec (query, null, out errmsg);
if (ec != Sqlite.OK) {
stderr.printf ("Error: %s\n", errmsg);
return -1;
}

int changes = db.total_changes ();
print ("Affected rows: %d\n", changes);

return 0;
}

valac --pkg sqlite3 delete.vala



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