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Diffstat (limited to 'lib/impure/db_postgres.nim')
| -rwxr-xr-x | lib/impure/db_postgres.nim | 166 |
1 files changed, 0 insertions, 166 deletions
diff --git a/lib/impure/db_postgres.nim b/lib/impure/db_postgres.nim deleted file mode 100755 index 131609a64..000000000 --- a/lib/impure/db_postgres.nim +++ /dev/null @@ -1,166 +0,0 @@ -# -# -# Nimrod's Runtime Library -# (c) Copyright 2010 Andreas Rumpf -# -# See the file "copying.txt", included in this -# distribution, for details about the copyright. -# - -## A higher level `PostgreSQL`:idx: database wrapper. This interface -## is implemented for other databases too. - -import strutils, postgres - -type - TDbConn* = PPGconn ## encapsulates a database connection - TRow* = seq[string] ## a row of a dataset - EDb* = object of EIO ## exception that is raised if a database error occurs - - TSqlQuery* = distinct string ## an SQL query string - -proc sql*(query: string): TSqlQuery {.noSideEffect, inline.} = - ## constructs a TSqlQuery from the string `query`. This is supposed to be - ## used as a raw-string-literal modifier: - ## ``sql"update user set counter = counter + 1"`` - ## - ## If assertions are turned off, it does nothing. If assertions are turned - ## on, later versions will check the string for valid syntax. - result = TSqlQuery(query) - -proc dbError(db: TDbConn) {.noreturn.} = - ## raises an EDb exception. - var e: ref EDb - new(e) - e.msg = $PQerrorMessage(db) - raise e - -proc dbError*(msg: string) {.noreturn.} = - ## raises an EDb exception with message `msg`. - var e: ref EDb - new(e) - e.msg = msg - raise e - -proc dbQuote(s: string): string = - result = "'" - for c in items(s): - if c == '\'': add(result, "''") - else: add(result, c) - add(result, '\'') - -proc dbFormat(formatstr: TSqlQuery, args: openarray[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: TDbConn, query: TSqlQuery, - args: openarray[string]): bool = - ## tries to execute the query and returns true if successful, false otherwise. - var q = dbFormat(query, args) - var res = PQExec(db, q) - result = PQresultStatus(res) == PGRES_COMMAND_OK - PQclear(res) - -proc Exec*(db: TDbConn, query: TSqlQuery, args: openarray[string]) = - ## executes the query and raises EDB if not successful. - var q = dbFormat(query, args) - var res = PQExec(db, q) - if PQresultStatus(res) != PGRES_COMMAND_OK: dbError(db) - PQclear(res) - -proc newRow(L: int): TRow = - newSeq(result, L) - for i in 0..L-1: result[i] = "" - -proc setupQuery(db: TDbConn, query: TSqlQuery, - args: openarray[string]): PPGresult = - var q = dbFormat(query, args) - result = PQExec(db, q) - if PQresultStatus(result) != PGRES_TUPLES_OK: dbError(db) - -proc setRow(res: PPGresult, r: var TRow, line, cols: int) = - for col in 0..cols-1: - setLen(r[col], 0) - var x = PQgetvalue(res, line, col) - add(r[col], x) - -iterator FastRows*(db: TDbConn, query: TSqlQuery, - args: openarray[string]): TRow = - ## executes the query and iterates over the result dataset. This is very - ## fast, but potenially dangerous: If the for-loop-body executes another - ## query, the results can be undefined. For Postgres it is safe though. - var res = setupQuery(db, query, args) - var L = int(PQnfields(res)) - var result = newRow(L) - for i in 0..PQntuples(res)-1: - setRow(res, result, i, L) - yield result - PQclear(res) - -proc GetAllRows*(db: TDbConn, query: TSqlQuery, - args: openarray[string]): seq[TRow] = - ## executes the query and returns the whole result dataset. - result = @[] - for r in FastRows(db, query, args): - result.add(r) - -iterator Rows*(db: TDbConn, query: TSqlQuery, - args: openarray[string]): TRow = - ## same as `FastRows`, but slower and safe. - for r in items(GetAllRows(db, query, args)): yield r - -proc GetValue*(db: TDbConn, query: TSqlQuery, - args: openarray[string]): string = - ## executes the query and returns the result dataset's the first column - ## of the first row. Returns "" if the dataset contains no rows. - var x = PQgetvalue(setupQuery(db, query, args), 0, 0) - result = if isNil(x): "" else: $x - -proc TryInsertID*(db: TDbConn, query: TSqlQuery, - args: openarray[string]): int64 = - ## executes the query (typically "INSERT") and returns the - ## generated ID for the row or -1 in case of an error. For Postgre this adds - ## ``RETURNING id`` to the query, so it only works if your primary key is - ## named ``id``. - var val = GetValue(db, TSqlQuery(string(query) & " RETURNING id"), args) - if val.len > 0: - result = ParseBiggestInt(val) - else: - result = -1 - -proc InsertID*(db: TDbConn, query: TSqlQuery, - args: openArray[string]): int64 = - ## executes the query (typically "INSERT") and returns the - ## generated ID for the row. For Postgre this adds - ## ``RETURNING id`` to the query, so it only works if your primary key is - ## named ``id``. - result = TryInsertID(db, query, args) - if result < 0: dbError(db) - -proc ExecAffectedRows*(db: TDbConn, query: TSqlQuery, - args: openArray[string]): int64 = - ## executes the query (typically "UPDATE") and returns the - ## number of affected rows. - var q = dbFormat(query, args) - var res = PQExec(db, q) - if PQresultStatus(res) != PGRES_COMMAND_OK: dbError(db) - result = parseBiggestInt($PQcmdTuples(res)) - PQclear(res) - -proc Close*(db: TDbConn) = - ## closes the database connection. - if db != nil: PQfinish(db) - -proc Open*(connection, user, password, database: string): TDbConn = - ## opens a database connection. Raises `EDb` if the connection could not - ## be established. - result = PQsetdbLogin(nil, nil, nil, nil, database, user, password) - if PQStatus(result) != CONNECTION_OK: dbError(result) # result = nil - - |