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- Usage of regexp_replace in oracle
- The REGEXP_REPLACE function in Oracle replaces matching parts of a string using regular expressions: Syntax: REGEXP_REPLACE(input_string, pattern, replacement) Usage example: Replace all numbers with X Replace all vowels with A Replace with capturing groups Advanced usage: Replace Count ignore case multiline mode
- Oracle 913 2024-05-02 23:36:51
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- How to delete a field in a table in oracle
- Deleting a field from a table in Oracle requires the following steps: Determine the field to delete. Use the ALTER TABLE table_name DROP COLUMN column_name statement. Commit changes. After a field is deleted, it will not be restored and dependencies need to be checked and adjusted.
- Oracle 868 2024-05-02 23:36:16
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- What is the length of number in oracle
- The Oracle NUMBER data type has a maximum length of 38 bits, including the decimal point and decimal places: 38 bits for the integer part and 128 bits for the fractional part. Precision is the number of digits that can be stored after the decimal point and ranges from 0 to 128. When choosing the appropriate length, consider data range, accuracy requirements, and storage space.
- Oracle 629 2024-05-02 23:33:59
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- What does sp mean in oracle?
- SPSP in Oracle stands for Stored Procedure and is used to encapsulate complex blocks of SQL statements into reusable modules. The advantages of stored procedures include: code reusability, improved performance, improved data integrity, and improved security.
- Oracle 972 2024-05-02 23:33:40
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- Extend usage in oracle
- Oracle's EXTEND operator is used to allocate storage space to an existing partition in a partitioned table, increasing its size. Syntax: ALTER TABLE table_name EXTEND PARTITION partition_name FOR { storage (size) | MAXSIZE (size) }. Parameters include partition table name, partition name, storage space size or maximum storage space size, etc. The EXTEND operator extends indexes with USING INDEXES and excludes partitions with NOT INCLUDING PARTITION. Execute EX online or offline
- Oracle 312 2024-05-02 23:33:21
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- The difference between date and timestamp in oracle
- DATE in Oracle stores only the date part, accurate to days, while TIMESTAMP stores date and time parts, accurate to microseconds, and can store time zone offsets. They also differ in storage space, scope and format. Best practice is to choose the appropriate type based on the information you need to store: use DATE if you need only date information, or TIMESTAMP if you need precise time and time zone information.
- Oracle 876 2024-05-02 23:30:26
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- What is rownum in oracle
- ROWNUM in Oracle is a pseudo column that represents the row sequence number in the current query result. It is mainly used for paging queries, row number display and avoiding duplicate data.
- Oracle 1205 2024-05-02 23:27:53
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- How to arrange in reverse order in oracle
- In Oracle, reverse sorting can be achieved through the ORDER BY clause: use the ORDER BY column_name DESC syntax, where column_name is the name of the column to be sorted. For example: SELECT first_name, last_name FROM employees ORDER BY last_name DESC.
- Oracle 1046 2024-05-02 23:24:52
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- Decimal usage in oracle
- The Oracle DECIMAL data type provides high-precision storage of decimal values for calculations that require precision. Features include: Configurable precision, variable length between 1 and 38, based on precision and range High precision, accurate calculations of currencies, scientific data, etc. Immutable, values cannot be changed after they are created
- Oracle 1029 2024-05-02 23:24:37
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- How to use unique in oracle
- The UNIQUE constraint in Oracle ensures that a specific column or combination of columns in the table has a unique value, preventing duplicate data insertion. It is implemented through the following rules: 1. In an insert or update operation, the value of a specified column or column combination cannot be repeated with an existing value; 2. Indexes are allowed to be created to improve query efficiency.
- Oracle 1008 2024-05-02 23:24:17
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- and usage in oracle
- The AND operator is used to combine conditions in Oracle and returns TRUE if all conditions are TRUE and FALSE otherwise. Usage includes: Combining simple conditions Nested conditions to create complex conditions Combined with the NOT operator to create negative conditions Have higher precedence than the OR operator
- Oracle 1007 2024-05-02 23:22:00
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- Usage of any and all in oracle
- ANY and ALL are operators used in Oracle for conditional checking of set elements. ANY checks whether any element in the set satisfies the condition, ALL checks whether all elements satisfy the condition. ANY is often used to find any item that satisfies a condition, while ALL is used to verify that all items satisfy the condition.
- Oracle 955 2024-05-02 23:21:37
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- What does union mean in oracle?
- UNION is a data manipulation language command that vertically combines the results of two or more SELECT statements but retains only unique rows. It requires that the result sets of the merged SELECT statements have the same number of columns and data types, and can only handle compatible data types (for example, you cannot combine numeric columns with string columns).
- Oracle 1113 2024-05-02 23:21:17
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- Alternative way of writing union in oracle
- Alternatives to UNION in Oracle include: Direct addition (+): joins query results, retaining duplicate rows. UNION ALL: Join query results, retaining all rows. WITH subquery: Create a temporary table, contain the query results, and then query the temporary table. CTE: Define temporary tables or views for subsequent queries. SQL JOIN: Join related rows in multiple tables.
- Oracle 513 2024-05-02 23:18:50
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- How to use replace function in oracle
- The REPLACE function in Oracle is used to replace a specified substring in a string with another substring. The methods of use include: 1. Replace errors or spelling errors in the text; 2. Change the content of the string; 3. From characters Remove a specific substring from a string.
- Oracle 1165 2024-05-02 23:18:32
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