code:
select * from table where column1 = :value1 and column2 = :value2 or column3 = :value3

Quote:

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NULL or TRUE = TRUE
NULL and TRUE = NULL

...
select (1 = 1) from dual

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Quote:

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имхо ты сам себе противоречишь

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code:

where column ~= :value

code:

where NVL(column, SPECIAL_VALUE_THAT_NEVER_CAN_OCCURS_IN_THIS_COLUMN)
 = NVL(:value, SPECIAL_VALUE_THAT_NEVER_CAN_OCCURS_IN_THIS_COLUMN)

В ответ на:

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и первое и второе - это чисто oracle, а не sql

в sql в первом случае должно быть: null or true - null

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Quote:

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Boolean datatype inconsistency
The ISO SQL:1999 standard introduced the Boolean datatype to SQL.[20] The Boolean datatype, as defined by the standard, can hold the truth values TRUE, FALSE, and UNKNOWN. Null is defined in this one instance as equivalent to the truth value UNKNOWN.

This "null equals UNKNOWN truth value" proposition introduces an inconsistency into SQL 3VL. One major problem is that it contradicts a basic property of nulls, the property of propagation. Nulls, by definition, propagate through all SQL expressions. The Boolean truth values do not have this property. Consider the following scenarios in SQL:1999, in which two Boolean truth values are combined into a compound predicate. According to the rules of SQL 3VL, and as shown in the 3VL truth table shown earlier in this article, the following statements hold:

( TRUE OR UNKNOWN ) → TRUE
( FALSE AND UNKNOWN ) → FALSE
However, because nulls propagate, treating null as UNKNOWN results in the following logical inconsistencies in SQL 3VL:

( TRUE OR NULL ) → NULL ( = UNKNOWN )
( FALSE AND NULL ) → NULL ( = UNKNOWN )
The SQL:1999 standard does not define how to deal with this inconsistency, and results could vary between implementations. Because of these inconsistencies and lack of support from vendors the SQL Boolean datatype did not gain widespread acceptance. Most SQL DBMS platforms now offer their own platform-specific recommendations for storing Boolean-type data.

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В ответ на:

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Если в базе есть клиенты с именем NULL, они и должны получиться.

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Quote:

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Люди, работающие по несколько лет исключительно с базами данных, офигевают, когда узнают, что

code:
NULL or TRUE = TRUE
NULL and TRUE = NULL

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Quote:

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Я знаю их настолько, насколько мне это сейчас нужно.
Понадобится лучше - будет лучше.

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В ответ на:

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Тогда ты никого и не получишь

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В ответ на:

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Если имени нет, то храни там пустую строку. Или FALSE или UNKNOWN, смотря что БД позволяет использовать.

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