56 lines
1.5 KiB
Plaintext
56 lines
1.5 KiB
Plaintext
m4_comment([$Id: db_exists.so,v 1.1 2007/07/12 18:27:42 bostic Exp $])
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define(M4PAGELOCAL, dbh_exists)
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include(m4/m4.seealso)
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m4_pf_header(m4_ref(dbh_exists),
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ifelse(M4API, C_API, [dnl
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int
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DB-__GT__exists(DB *db, DB_TXN *txnid, DBT *key, u_int32_t flags);
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])
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ifelse(M4API, CXX_API, [dnl
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int
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Db::exists(DbTxn *txnid, Dbt *key, u_int32_t flags);
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]))
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m4_p([dnl
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The m4_refT(dbh_exists) returns if the specified key appears in the
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database.])
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m4_return(dbh_exists,
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specific, DB_NOTFOUND, [if the specified key is not in the database],
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specific, DB_KEYEMPTY, [if the database is a Queue or Recno database and
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the specified key exists, but was never explicitly created by the
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application or was later deleted], prev)
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m4_parambegin
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m4_param(flags, [dnl
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m4_sf_zmust(1)
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m4_sf_or_add(1)
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m4_tagbegin
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m4_tag(m4_idef(DB_READ_COMMITTED), [dnl
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Configure a transactional read operation to have degree 2 isolation (the
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read is not repeatable).])
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m4_tag(m4_idef(DB_READ_UNCOMMITTED), [dnl
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Configure a transactional read operation to have degree 1 isolation,
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reading modified but not yet committed data. Silently ignored if the
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m4_ref(DB_READ_UNCOMMITTED) flag was not specified when the underlying
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database was opened.])
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m4_rmw_flag([Because the m4_refT(dbh_exists) will not hold locks across
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m4_db calls in non-transactional operations, the m4_ref(DB_RMW) flag to
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the m4_ref(dbh_exists) call is meaningful only in the presence of
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transactions.])
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m4_tagend])
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m4_param_key
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m4_param_txn(dbh_exists, ro)
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m4_paramend
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m4_seealso(Db)
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m4_page_footer
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