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package sqlite3
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import "database/sql"
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// statements holds prepared statements for fixed-shape queries.
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// Reader statements are prepared on s.reader; writer statements on s.writer.
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// For transactional writes, callers use tx.StmtContext to bind a prepared
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// statement into the active transaction.
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type statements struct {
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	// -- reader --
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	simpleGet      *sql.Stmt
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	prefixContains *sql.Stmt
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	prefixList     *sql.Stmt
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	listKeys       *sql.Stmt
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	rangeKeysNorm  *sql.Stmt
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	rangeKeysWrap  *sql.Stmt
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	// -- writer --
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	simplePut    *sql.Stmt
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	simpleDel    *sql.Stmt
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	prefixAppend *sql.Stmt
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	prefixRemove *sql.Stmt
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	prefixCount  *sql.Stmt
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	leaseAcquire *sql.Stmt
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	leaseRenew   *sql.Stmt
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	leaseRelease *sql.Stmt
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	leaseGet     *sql.Stmt
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	leaseImport  *sql.Stmt
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	trackerLookup *sql.Stmt
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	trackerInsert *sql.Stmt
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	trackerUpdate *sql.Stmt
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	trackerDelete *sql.Stmt
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	// export uses the reader inside a read tx
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	exportSimpleGet  *sql.Stmt
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	exportPrefixList *sql.Stmt
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	exportLeaseGet   *sql.Stmt
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	all []*sql.Stmt
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}
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func prepareStatements(reader, writer *sql.DB) (_ *statements, err error) {
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	s := &statements{}
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	defer func() {
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		if err != nil {
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			s.close()
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		}
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	}()
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	type preparedStatement struct {
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		db     *sql.DB
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		query  string
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		target **sql.Stmt
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	}
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	defs := []preparedStatement{
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		{reader, querySimpleGet, &s.simpleGet},
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		{reader, queryPrefixContains, &s.prefixContains},
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		{reader, queryPrefixList, &s.prefixList},
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		{reader, queryListKeys, &s.listKeys},
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		{reader, queryRangeKeysNorm, &s.rangeKeysNorm},
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		{reader, queryRangeKeysWrap, &s.rangeKeysWrap},
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		{writer, querySimplePut, &s.simplePut},
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		{writer, querySimpleDel, &s.simpleDel},
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		{writer, queryPrefixAppend, &s.prefixAppend},
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		{writer, queryPrefixRemove, &s.prefixRemove},
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		{writer, queryPrefixCount, &s.prefixCount},
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		{writer, queryLeaseAcquire, &s.leaseAcquire},
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		{writer, queryLeaseRenew, &s.leaseRenew},
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		{writer, queryLeaseRelease, &s.leaseRelease},
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		{writer, queryLeaseGet, &s.leaseGet},
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		{writer, queryLeaseImport, &s.leaseImport},
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		{writer, queryTrackerLookup, &s.trackerLookup},
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		{writer, queryTrackerInsert, &s.trackerInsert},
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		{writer, queryTrackerUpdate, &s.trackerUpdate},
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		{writer, queryTrackerDelete, &s.trackerDelete},
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		{reader, queryLeaseGet, &s.exportLeaseGet},
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	}
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	for _, def := range defs {
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		st, prepErr := def.db.Prepare(def.query)
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		if prepErr != nil {
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			err = prepErr
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			return nil, err
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		}
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		*def.target = st
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		s.all = append(s.all, st)
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	}
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	s.exportSimpleGet = s.simpleGet
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	s.exportPrefixList = s.prefixList
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	return s, nil
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}
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func (s *statements) close() {
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	if s == nil {
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		return
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	}
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	for _, st := range s.all {
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		if st != nil {
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			_ = st.Close()
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		}
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	}
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	s.all = nil
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}