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- Instr usage in oracle
- The function of the INSTR function in Oracle is to find the starting position of a substring in a string. The syntax is INSTR(string, substring, [start_position]). It returns the starting position of the matching substring. If it is not found, it returns 0. Among them, string is the string to be searched, substring is the substring to be found, and start_position is the starting position of the search (optional). The INSTR function is not case-sensitive. By default, it searches from the beginning of the string. It supports searching from the specified position. If the substring appears multiple times in the string, only the starting position of the first matching item will be returned. If the string or subword
- Oracle 971 2024-05-02 23:54:57
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- How to use insert in oracle
- The INSERT statement in Oracle is used to insert new rows into the table. The syntax is: INSERT INTO table_name (column1, column2, ...) VALUES (value1, value2, ...), where table_name is the table name, column1, column2, ... is the column name, value1, value2, ... are values. Multiple rows can be inserted. NULL values must be inserted. The values must be compatible with the data type. Repeated primary key values cannot be inserted. The defined trigger will be triggered. If not Specifying column names will insert them in table column order.
- Oracle 1031 2024-05-02 23:54:37
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- How to use if function in oracle
- The IF function in Oracle is a control flow function used to execute blocks of code based on conditions. Its syntax is as follows: IF (condition) THEN -- If the condition is true, execute this code block ELSE -- If the condition is false, execute this code block END IF;
- Oracle 1179 2024-05-02 23:54:20
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- How to write when and then in oracle
- In Oracle, the WHEN and THEN syntax is used in CASE expressions to return different values based on a condition: The WHEN clause specifies the condition to be evaluated. The THEN clause specifies the value to be returned if the condition is true. The ELSE clause (optional) specifies the value returned when all WHEN conditions are false.
- Oracle 1152 2024-05-02 23:51:52
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- Usage of lag (function and lead (function) in oracle
- The LAG() and LEAD() functions in Oracle obtain the value of the row before (LAG()) or after (LEAD()) the specified row offset from the current row. They are used to analyze time series data and calculate moving averages. The LAG() function returns the value of the previous row, and the LEAD() function returns the value of the subsequent row. The offset can be positive or negative, and returns a default value if it is outside the table range.
- Oracle 1152 2024-05-02 23:51:36
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- count usage in oracle
- The COUNT function is used to count the number of rows in the table that meet the conditions. Syntax: COUNT(DISTINCT|ALL expression); where: DISTINCT counts unique values, ALL counts all values. Usage includes counting the number of all rows, the number of non-null values in a specific column, the number of rows that meet the condition, and the number of unique values.
- Oracle 946 2024-05-02 23:48:58
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- The difference between concat function and || in oracle
- CONCAT and || are both string connection functions in Oracle. The main differences are: function syntax (CONCAT with parentheses, || without), NULL processing (CONCAT returns NULL, || returns an empty string), performance (CONCAT is more Slow) and usage scenarios (CONCAT is used for multi-string concatenation that may have NULL, || is used for small-string concatenation without NULL).
- Oracle 1077 2024-05-02 23:48:37
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- How to use concat function in oracle
- The CONCAT function in Oracle is used to concatenate strings: Concatenate multiple strings: CONCAT(string1, string2, ...) Concatenate strings and column values: CONCAT('text', column name) Concatenate strings using operators: 'string1' || 'string2' || ...Note: If any string is NULL, the result is NULL; up to 254 strings can be concatenated.
- Oracle 1018 2024-05-02 23:46:11
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- Tochar usage in oracle
- The TO_CHAR function converts an Oracle expression to a character value, formatting the output to suit your needs. Use a string template (format_mask) to define the format, including text characters, format modifiers, and placeholders. Format masks are case-sensitive, and placeholders require the correct format modifier.
- Oracle 1051 2024-05-02 23:45:33
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- How to add two decimal points to an integer in Oracle?
- There are two ways to represent integers with two decimal points in Oracle: scientific notation (such as 100 * 10^-2 = 0.01) and the TO_CHAR function (such as TO_CHAR(100, 'fm9999999999990.99') = 0.01).
- Oracle 597 2024-05-02 23:42:52
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- How to use case in oracle
- The CASE statement in Oracle is a tool for conditional evaluation, its usage includes: specifying the condition to be evaluated (WHEN). The action (THEN) to perform if the condition is true. If all conditions are false, perform the default action (ELSE, optional).
- Oracle 871 2024-05-02 23:42:36
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- What does number(10,4) mean in oracle
- The NUMBER(10,4) data type in Oracle stores numeric values with a precision of 4 decimal places, ranging from -9999999999.9999 to 9999999999.9999. The maximum length of the integer part is 6 digits, and the maximum length of the decimal part is 4 digits.
- Oracle 883 2024-05-02 23:42:17
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- Usage of to_date in oracle
- The TO_DATE function in Oracle converts a string to the DATE data type. Syntax: TO_DATE(string, format_mask). format_mask is a placeholder mask that specifies the format of the date and time portion of the string. Placeholders include YYYY (year), MM (month), DD (day), HH (hour), MI (minute), SS (second), FF (billionth of a second). For example, TO_DATE('2023-03-08', 'YYYY-MM-DD') converts "2023-03-08" to DATE.
- Oracle 899 2024-05-02 23:40:00
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- Usage of todate function in oracle
- The TO_DATE function converts a string to an Oracle date type. It takes two parameters: the string expression to convert and a format mask specifying the string format. Common format masks include 'DD-MON-YY' (e.g. '12-JAN-23'), 'YYYY-MM-DD' (e.g. '2023-01-12') and 'HH24:MI:SS' (e.g. '12-JAN-23') For example '13:30:00'). Use a format mask to select the correct format to convert a string into a date value.
- Oracle 559 2024-05-02 23:39:40
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- How to use on in oracle
- The ON clause joins rows in a table, creating a matching relationship based on common columns. It is used in table join operations, and the syntax is: ON <join_condition>. This condition compares columns in the table to establish the connection.
- Oracle 689 2024-05-02 23:39:19
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