Posts (page 4)
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6 min readThere are several strategies that can be implemented to improve the performance of Oracle inserts.One approach is to use bulk insert operations instead of single row inserts. This can be achieved by using the INSERT INTO ... SELECT syntax or by using the FORALL statement in PL/SQL to process multiple rows at once.Another strategy is to minimize the number of indexes on the table being inserted into, as each index adds overhead to the insert operation.
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5 min readTo create a table based on multiple tables in Oracle, you can use the CREATE TABLE AS statement. This statement allows you to create a new table by selecting data from one or more existing tables. You can specify the columns you want to include in the new table and use queries to extract data from the multiple tables.For example, you can create a new table by combining data from two existing tables using a query like this: CREATE TABLE new_table AS SELECT table1.column1, table1.column2, table2.
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5 min readTo modify an array under a specific JSONB key in PostgreSQL, you can use the jsonb_set function. This function allows you to specify the path to the key you want to modify and update the array under that key.
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4 min readTo filter a PostgreSQL query by date using Python, you can use the psycopg2 library to connect to the database and execute SQL queries. You can specify the date range using the WHERE clause in your query. For example, if you want to filter records that fall within a specific date range, you can use the following syntax: import psycopg2 conn = psycopg2.connect("dbname=mydb user=postgres password=secret") cur = conn.
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3 min readIn PostgreSQL, you can cast a string into an integer by using the CAST function or the :: operator. For example, if you have a string '123' and you want to convert it into an integer, you can do so by using either of the following queries:Using the CAST function: SELECT CAST('123' AS INTEGER); Using the :: operator: SELECT '123'::INTEGER; Both of these queries will convert the string '123' into an integer value of 123.
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4 min readTo export a JSONB column in PostgreSQL, you can use the jsonb_to_json function to convert the JSONB data into JSON format. Then, you can use the jsonb_pretty function if you want to pretty print the JSON data. Finally, you can use the COPY command to export the JSON data to a file or another location. By combining these functions and commands, you can easily export JSONB data from a PostgreSQL table.
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3 min readIn PostgreSQL, you can convert a bigint value representing a timestamp into a formatted date string using the TO_TIMESTAMP function along with the TO_CHAR function.First, you need to cast the bigint value to a timestamp using the TO_TIMESTAMP function. For example, if your bigint value is stored in a column named "timestamp_column" in a table called "example_table", you can convert it to a timestamp like this:TO_TIMESTAMP(example_table.
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4 min readTo count every entry for each day in PostgreSQL, you can use the GROUP BY clause in combination with the COUNT function. By grouping the entries by the date field and then using COUNT, you can easily determine the number of entries for each day. Remember to also include the appropriate date formatting function to extract the date from the timestamp column if needed. Additionally, you can further filter the results by specific dates or date ranges by using the WHERE clause in your query.
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5 min readTo select from a variable in PostgreSQL, you first need to declare and set the variable using the PL/pgSQL language. This can be done using the := operator. Once the variable is set, you can then use it in your SQL query by referencing the variable name.
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8 min readIn PostgreSQL, you can use multiple partitions to store your data in a more organized manner. This can help with managing large amounts of data more efficiently. To use multiple partitions in PostgreSQL, you first need to create a partitioned table. This table will act as the parent table for your partitions.Next, you need to create child tables that will hold the actual data for each partition.
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3 min readTo select from a variable in PostgreSQL, you can use the SELECT statement along with the variable name. You need to declare the variable first using the DO $$ syntax. Then you can assign a value to the variable within the PostgreSQL PL/pgSQL block. Once the variable is defined and assigned a value, you can use it in your SELECT statement to retrieve data from the database based on the variable's value.
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6 min readTo execute a PostgreSQL stored procedure, you can use the CALL or SELECT statement depending on the return type of the procedure. If the procedure returns a result set, you can use the SELECT statement to execute it. For example: SELECT * FROM my_stored_procedure();If the procedure does not return a result set, you can use the CALL statement to execute it. For example: CALL my_stored_procedure();Make sure to replace my_stored_procedure with the actual name of your stored procedure.