Year: 2023
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Post Views: 16 1. In Laravel 6, you need to query the penultimate record. as shown in Figure 1 2. Based on the reverse order, use LIMIT, the code is implemented as follows 3. The printing results are in line with expectations. as shown in Figure 2
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Post Views: 17 1. Decide to make the band in the strategic transaction under the BTC perpetual contract. 2. BTCUSDT Sustainable Neutral 20.00X, the price range (USDT) are respectively 25,000-28,000, 28,000-31,000, 31,000-34,000, time range: 05/26 – 08/20, total close to 3 Month time, margin $900, total income (USDT): 209.8305 + 160.105 + 21.4504 = 391.3859. Yield: 43%. As shown in…
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Post Views: 17 1. The json field is stored in the array format, the value example:[249, 247, 250, 244, 243, 255, 246, 245, 257, 248, 259, 252, 256]. as shown in Figure 1 2. The existing code running in the queue job is implemented as follows, the generated SQL is as follows 3. Since the queue tasks can be run…
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Post Views: 18 1. Add elements to a specific position in the index array, and now plan to add 2 elements, after price. 2. Based on array_splice — remove a part of the array and replace it with other values, the code is implemented as follows, 3. Print the running results, in line with expectations. as shown in Figure 1…
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Post Views: 21 1. In the NetEase Mail Master app, the mailing list prompts: There is no text content in this email, please click to view more details of the email content. as shown in Figure 1 2. Click to enter the email details in the NetEase Mail Master app, prompt: Password verification failed shuijingwanwq@gmail.com password verification failed, please re-authenticate.…
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Post Views: 17 1. When the Stop Profit Stop Order is placed in the Ouyi APP, it is prompted: The market price of the currency and the leveraged Stop-Profit Stop Order is temporarily unavailable. as shown in Figure 1 2. Adjust the market price take profit to limit price take profit. as shown in Figure 2 3. The order is…
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Post Views: 13 1. The field table2_id in the table table1 is associated with the primary key field ID of the table table2. Now you need to query data that exists in table table1 but not in table table2 . The final implementation of SQL is as follows. as shown in Figure 1
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Post Views: 19 1. When deleting the table in MySQL, an error is reported: 1217 – Cannot delete or update a parent row: a foreign key constraaint fail. as shown in Figure 1 2. Reference:You can get information about foreign keys from information_schema.key_column_usagetable. The query example for that table is shown here . as shown in Figure 2 3. The…
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Post Views: 55 1. In the table, there is a large amount of duplicate data in the column store_name, such as: chill26, ftolrxs34. as shown in Figure 1 2. Now I want to count how many non-repeatable store_name are in total. Then you need to remove the duplicate data first to ensure the uniqueness of each row. Reference:Use duplicates quickly…