Oracle DBA Lesson 22A — Where Did Startup Stop?

Oracle starts in three stages: NOMOUNT, MOUNT, and OPEN. Each stage needs different files. The stage Oracle reached is why the database...

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Oracle DBA Lesson 21E — Why Dates and Numbers Look Different

A DATE is not the characters on the screen. SQL*Plus turns that value into text with the session's date mask, so one stored day pri...

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Oracle DBA Lesson 21D — Why Text Looks Wrong in SQL*Plus

SQL*Plus does not decide what your keyboard sends. It tells Oracle what those bytes already are, in NLS_LANG . Oracle converts betwee...

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Oracle DBA Lesson 21C — Characters, Bytes, and Text-Column Limits

José is four characters and, in an AL32UTF8 database, five bytes. LENGTH counts the characters. LENGTHB counts the bytes. A VARCHAR2...

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