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Diffstat (limited to 'lib/impure/db_sqlite.nim')
| -rw-r--r-- | lib/impure/db_sqlite.nim | 338 |
1 files changed, 0 insertions, 338 deletions
diff --git a/lib/impure/db_sqlite.nim b/lib/impure/db_sqlite.nim deleted file mode 100644 index fd25b2b94..000000000 --- a/lib/impure/db_sqlite.nim +++ /dev/null @@ -1,338 +0,0 @@ -# -# -# Nim's Runtime Library -# (c) Copyright 2015 Andreas Rumpf -# -# See the file "copying.txt", included in this -# distribution, for details about the copyright. -# - -## A higher level `SQLite`:idx: database wrapper. This interface -## is implemented for other databases too. -## -## See also: `db_odbc <db_odbc.html>`_, `db_postgres <db_postgres.html>`_, -## `db_mysql <db_mysql.html>`_. -## -## Parameter substitution -## ---------------------- -## -## All ``db_*`` modules support the same form of parameter substitution. -## That is, using the ``?`` (question mark) to signify the place where a -## value should be placed. For example: -## -## .. code-block:: Nim -## sql"INSERT INTO myTable (colA, colB, colC) VALUES (?, ?, ?)" -## -## Examples -## -------- -## -## Opening a connection to a database -## ================================== -## -## .. code-block:: Nim -## import db_sqlite -## let db = open("mytest.db", nil, nil, nil) # user, password, database name can be nil -## db.close() -## -## Creating a table -## ================ -## -## .. code-block:: Nim -## db.exec(sql"DROP TABLE IF EXISTS myTable") -## db.exec(sql("""CREATE TABLE myTable ( -## id integer, -## name varchar(50) not null)""")) -## -## Inserting data -## ============== -## -## .. code-block:: Nim -## db.exec(sql"INSERT INTO myTable (id, name) VALUES (0, ?)", -## "Jack") -## -## Larger example -## ============== -## -## .. code-block:: nim -## -## import db_sqlite, math -## -## let theDb = open("mytest.db", "", "", "") -## -## theDb.exec(sql"Drop table if exists myTestTbl") -## theDb.exec(sql("""create table myTestTbl ( -## Id INTEGER PRIMARY KEY, -## Name VARCHAR(50) NOT NULL, -## i INT(11), -## f DECIMAL(18,10))""")) -## -## theDb.exec(sql"BEGIN") -## for i in 1..1000: -## theDb.exec(sql"INSERT INTO myTestTbl (name,i,f) VALUES (?,?,?)", -## "Item#" & $i, i, sqrt(i.float)) -## theDb.exec(sql"COMMIT") -## -## for x in theDb.fastRows(sql"select * from myTestTbl"): -## echo x -## -## let id = theDb.tryInsertId(sql"INSERT INTO myTestTbl (name,i,f) VALUES (?,?,?)", -## "Item#1001", 1001, sqrt(1001.0)) -## echo "Inserted item: ", theDb.getValue(sql"SELECT name FROM myTestTbl WHERE id=?", id) -## -## theDb.close() - -{.deadCodeElim: on.} # dce option deprecated - -import strutils, sqlite3 - -import db_common -export db_common - -type - DbConn* = PSqlite3 ## encapsulates a database connection - Row* = seq[string] ## a row of a dataset. NULL database values will be - ## converted to nil. - InstantRow* = Pstmt ## a handle that can be used to get a row's column - ## text on demand -{.deprecated: [TRow: Row, TDbConn: DbConn].} - -proc dbError*(db: DbConn) {.noreturn.} = - ## raises a DbError exception. - var e: ref DbError - new(e) - e.msg = $sqlite3.errmsg(db) - raise e - -proc dbQuote*(s: string): string = - ## DB quotes the string. - if s.isNil: return "NULL" - result = "'" - for c in items(s): - if c == '\'': add(result, "''") - else: add(result, c) - add(result, '\'') - -proc dbFormat(formatstr: SqlQuery, args: varargs[string]): string = - result = "" - var a = 0 - for c in items(string(formatstr)): - if c == '?': - add(result, dbQuote(args[a])) - inc(a) - else: - add(result, c) - -proc tryExec*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): bool {. - tags: [ReadDbEffect, WriteDbEffect].} = - ## tries to execute the query and returns true if successful, false otherwise. - assert(not db.isNil, "Database not connected.") - var q = dbFormat(query, args) - var stmt: sqlite3.Pstmt - if prepare_v2(db, q, q.len.cint, stmt, nil) == SQLITE_OK: - let x = step(stmt) - if x in {SQLITE_DONE, SQLITE_ROW}: - result = finalize(stmt) == SQLITE_OK - -proc exec*(db: DbConn, query: SqlQuery, args: varargs[string, `$`]) {. - tags: [ReadDbEffect, WriteDbEffect].} = - ## executes the query and raises DbError if not successful. - if not tryExec(db, query, args): dbError(db) - -proc newRow(L: int): Row = - newSeq(result, L) - for i in 0..L-1: result[i] = "" - -proc setupQuery(db: DbConn, query: SqlQuery, - args: varargs[string]): Pstmt = - assert(not db.isNil, "Database not connected.") - var q = dbFormat(query, args) - if prepare_v2(db, q, q.len.cint, result, nil) != SQLITE_OK: dbError(db) - -proc setRow(stmt: Pstmt, r: var Row, cols: cint) = - for col in 0'i32..cols-1: - setLen(r[col], column_bytes(stmt, col)) # set capacity - setLen(r[col], 0) - let x = column_text(stmt, col) - if not isNil(x): add(r[col], x) - -iterator fastRows*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} = - ## Executes the query and iterates over the result dataset. - ## - ## This is very fast, but potentially dangerous. Use this iterator only - ## if you require **ALL** the rows. - ## - ## Breaking the fastRows() iterator during a loop will cause the next - ## database query to raise a DbError exception ``unable to close due to ...``. - var stmt = setupQuery(db, query, args) - var L = (column_count(stmt)) - var result = newRow(L) - while step(stmt) == SQLITE_ROW: - setRow(stmt, result, L) - yield result - if finalize(stmt) != SQLITE_OK: dbError(db) - -iterator instantRows*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): InstantRow - {.tags: [ReadDbEffect].} = - ## same as fastRows but returns a handle that can be used to get column text - ## on demand using []. Returned handle is valid only within the iterator body. - var stmt = setupQuery(db, query, args) - while step(stmt) == SQLITE_ROW: - yield stmt - if finalize(stmt) != SQLITE_OK: dbError(db) - -proc toTypeKind(t: var DbType; x: int32) = - case x - of SQLITE_INTEGER: - t.kind = dbInt - t.size = 8 - of SQLITE_FLOAT: - t.kind = dbFloat - t.size = 8 - of SQLITE_BLOB: t.kind = dbBlob - of SQLITE_NULL: t.kind = dbNull - of SQLITE_TEXT: t.kind = dbVarchar - else: t.kind = dbUnknown - -proc setColumns(columns: var DbColumns; x: PStmt) = - let L = column_count(x) - setLen(columns, L) - for i in 0'i32 ..< L: - columns[i].name = $column_name(x, i) - columns[i].typ.name = $column_decltype(x, i) - toTypeKind(columns[i].typ, column_type(x, i)) - columns[i].tableName = $column_table_name(x, i) - -iterator instantRows*(db: DbConn; columns: var DbColumns; query: SqlQuery, - args: varargs[string, `$`]): InstantRow - {.tags: [ReadDbEffect].} = - ## same as fastRows but returns a handle that can be used to get column text - ## on demand using []. Returned handle is valid only within the iterator body. - var stmt = setupQuery(db, query, args) - setColumns(columns, stmt) - while step(stmt) == SQLITE_ROW: - yield stmt - if finalize(stmt) != SQLITE_OK: dbError(db) - -proc `[]`*(row: InstantRow, col: int32): string {.inline.} = - ## returns text for given column of the row - $column_text(row, col) - -proc len*(row: InstantRow): int32 {.inline.} = - ## returns number of columns in the row - column_count(row) - -proc getRow*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} = - ## retrieves a single row. If the query doesn't return any rows, this proc - ## will return a Row with empty strings for each column. - var stmt = setupQuery(db, query, args) - var L = (column_count(stmt)) - result = newRow(L) - if step(stmt) == SQLITE_ROW: - setRow(stmt, result, L) - if finalize(stmt) != SQLITE_OK: dbError(db) - -proc getAllRows*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): seq[Row] {.tags: [ReadDbEffect].} = - ## executes the query and returns the whole result dataset. - result = @[] - for r in fastRows(db, query, args): - result.add(r) - -iterator rows*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} = - ## same as `FastRows`, but slower and safe. - for r in fastRows(db, query, args): yield r - -proc getValue*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): string {.tags: [ReadDbEffect].} = - ## executes the query and returns the first column of the first row of the - ## result dataset. Returns "" if the dataset contains no rows or the database - ## value is NULL. - var stmt = setupQuery(db, query, args) - if step(stmt) == SQLITE_ROW: - let cb = column_bytes(stmt, 0) - if cb == 0: - result = "" - else: - result = newStringOfCap(cb) - add(result, column_text(stmt, 0)) - else: - result = "" - if finalize(stmt) != SQLITE_OK: dbError(db) - -proc tryInsertID*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): int64 - {.tags: [WriteDbEffect], raises: [].} = - ## executes the query (typically "INSERT") and returns the - ## generated ID for the row or -1 in case of an error. - assert(not db.isNil, "Database not connected.") - var q = dbFormat(query, args) - var stmt: sqlite3.Pstmt - result = -1 - if prepare_v2(db, q, q.len.cint, stmt, nil) == SQLITE_OK: - if step(stmt) == SQLITE_DONE: - result = last_insert_rowid(db) - if finalize(stmt) != SQLITE_OK: - result = -1 - -proc insertID*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): int64 {.tags: [WriteDbEffect].} = - ## executes the query (typically "INSERT") and returns the - ## generated ID for the row. For Postgre this adds - ## ``RETURNING id`` to the query, so it only works if your primary key is - ## named ``id``. - result = tryInsertID(db, query, args) - if result < 0: dbError(db) - -proc execAffectedRows*(db: DbConn, query: SqlQuery, - args: varargs[string, `$`]): int64 {. - tags: [ReadDbEffect, WriteDbEffect].} = - ## executes the query (typically "UPDATE") and returns the - ## number of affected rows. - exec(db, query, args) - result = changes(db) - -proc close*(db: DbConn) {.tags: [DbEffect].} = - ## closes the database connection. - if sqlite3.close(db) != SQLITE_OK: dbError(db) - -proc open*(connection, user, password, database: string): DbConn {. - tags: [DbEffect].} = - ## opens a database connection. Raises `EDb` if the connection could not - ## be established. Only the ``connection`` parameter is used for ``sqlite``. - var db: DbConn - if sqlite3.open(connection, db) == SQLITE_OK: - result = db - else: - dbError(db) - -proc setEncoding*(connection: DbConn, encoding: string): bool {. - tags: [DbEffect].} = - ## sets the encoding of a database connection, returns true for - ## success, false for failure. - ## - ## Note that the encoding cannot be changed once it's been set. - ## According to SQLite3 documentation, any attempt to change - ## the encoding after the database is created will be silently - ## ignored. - exec(connection, sql"PRAGMA encoding = ?", [encoding]) - result = connection.getValue(sql"PRAGMA encoding") == encoding - -when not defined(testing) and isMainModule: - var db = open("db.sql", "", "", "") - exec(db, sql"create table tbl1(one varchar(10), two smallint)", []) - exec(db, sql"insert into tbl1 values('hello!',10)", []) - exec(db, sql"insert into tbl1 values('goodbye', 20)", []) - #db.query("create table tbl1(one varchar(10), two smallint)") - #db.query("insert into tbl1 values('hello!',10)") - #db.query("insert into tbl1 values('goodbye', 20)") - for r in db.rows(sql"select * from tbl1", []): - echo(r[0], r[1]) - for r in db.instantRows(sql"select * from tbl1", []): - echo(r[0], r[1]) - - db_sqlite.close(db) |